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The Human Factor
How Human Mistakes Can Cause
a Nuclear War
Lloyd J. Dumas,
Professor of Political Economy and Public Policy,
University of Texas at Dallas, Author, The Technology
Trap: Where Human Error and Malevolence Meet
Powerful Technologies (Praeger/ABC-CLIO, 2010)
(For SLMK Workshop at the World Congress of IP-
PNW: Basel, Switzerland, 28 August 2010)
Introduction
When the Cold War ended two decades ago,
we all breathed a collective sigh of relief. We
knew the world had not suddenly become a
peaceful place, but it seemed at least we had
managed to bring the nuclear arms race to a
close without the nightmare of nuclear war. By a
combination of good sense and good luck, we
had somehow exorcised the terrifying specter
that had haunted all of us since that mushroom
cloud first rose into the morning sky over Hiro-
shima.
Of course we knew the
arsenals of nuclear weap-
ons had not disappeared.
But that was just a matter
of time, a final detail, a
footnote to the history of
history’s most dangerous
arms race. Surely now we
would find a way to nego-
tiate a process that would
slowly but surely shrink
the accumulated nuclear
stockpiles of the existing
nuclear states, while insur-
ing against their prolifera-
tion to other countries.
Twenty years later, we live
in a world in which there
are more nuclear weapons states, not fewer, and
in which the major nuclear powers still stand
ready to launch thousands of nuclear weapons
at a moments notice. In the U.S., under the
leadership of a President who publicly supports
the goal of zero nuclear weapons, we have seen
record amounts of money budgeted to nurturing
American nuclear arsenals. The Cold War may
be over, but the Cold War mentality lives on.
The idea nuclear weapons can indefinitely keep
us safe through deterrence is an illusion, built
on yet another illusion we have yet to relinquish
--- the illusion that a species as prone to error
and malevolence as ours
can indefinitely control all
the technologies we create,
no matter how powerful, no
matter how dangerous, and
permanently avoid disaster.
No form of this illusion is
more threatening to human
survival than the belief that
we can indefinitely main-
tain arsenals of devastating
nuclear weapons without
eventually triggering nuclear
war, by intention or by mis-
take. The focus today is on
the role of human fallibility in
realizing the latter possibility,
nuclear war by accident.
We will begin by briefly
exploring the pervasiveness of human error, and
then consider the nature and genesis of acciden-
tal war. Finally, we will take a brief look at a
form of malevolence that links the possibility of
accidental nuclear war with what has become
a daily reality of present day life --- the threat of
Twenty years later, we live in a world
in which there are more nuclear
weapons states, not fewer, and in
which the major nuclear powers still
stand ready to launch thousands of
nuclear weapons at a moments no-
tice.
The Human Factor:
How Human Mistakes Could Cause a
Nuclear War
The Nuclear Umbrella Photo: Josefin Lind
terrorism. This link is malevolence in one of its
most virulent forms, the terrorism of mass destruc-
tion.
Human Error
Human error is a serious and pervasive problem.
Between 1950-2008, almost 30% of 1300 fatal
commercial airplane accidents worldwide were
caused by pilot error unrelated to weather or me-
chanical problems. A 1998 study by the Union
of Concerned Scientists of ten nuclear power
plants (representing a cross section of American
civilian nuclear industry) concluded that nearly
80% of reported problems resulted from worker
mistakes or the use of poorly designed proce-
dures. On July 20, 2006, the U.S. National Insti-
tute of Medicine released a report indicating that
1.5 million people are hurt and several thousand
are killed every year in the U.S. as a result of
errors in medication. The New York Times report-
ed, “Drug errors are so widespread that hospi-
tal patients should expect to suffer one every day
they remain hospitalized.”
As we briefly survey some of the most important
aspects of human error in dangerous technologi-
cal systems, keep two key points in mind. The
first is that failures do not have to be continuous
in order to be dangerous. A drug or alcohol im-
paired nuclear weapons guard is not a problem
most of the time, because most of the time noth-
ing happens. But if that guard is not alert and
ready to act the moment terrorist commandos try
to break into the storage area, there could be a
major disaster. Because there is no way to know
when those critical moments will occur, every
failure of reliability must be taken seriously.
The second point is that the difference between
a trivial error and a catastrophic error lies not in
the error itself, but in the surrounding situation.
Many of the most trivial kinds of mistakes that all
of us make on a daily basis would be disastrous
if made in a very different context. For example,
making a telephone call begins by entering a se-
quence of numbers on a keypad that is fed into
computers that switch the call. If we enter the
wrong number, we get the wrong person. The
error is trivial. But on a clear night in December
1995, the pilots of American Airlines Flight 965
made essentially the same mistake as they were
flying toward Cali, Colombia. They entered the
wrong sequence of numbers into a computer, the
plane’s navigational computer. The plane steered
into the side of mountain, and 160 people died.
Boredom
For all the potential risk involved, much of the
day-to-day work of many of those who deal with
dangerous technologies is really quite boring.
Guarding nuclear weapons storage areas, going
through checklists in missile silos, monitoring con-
trol panels at nuclear power plants is not all that
stimulating. Boring work dulls the mind, leading
to a lack of vigilance. Laboratory studies have
shown that, after a few weeks, people exposed
to extremely monotonous living and working en-
vironments sometimes experience serious mood
swings, diminished judgment, and even halluci-
nations.
The things people sometimes feel driven to do to
cope with grinding boredom can also cause seri-
ous reliability problems. They may try to distract
themselves by focusing their attention on more
interesting or amusing thoughts, which means
they are not paying close attention to the task at
hand. They may play games. For example, in
the late 1970s, Tooele Army Depot in Utah con-
Lloyd J. Dumas at the IPPNW World Congress 28 August 2010
Photo: Josefin Lind
tained enough GB and VX nerve gas to kill the
population of the earth 100 times over. Accord-
ing to newspaper reports, the guards at Tooele
sometimes distracted themselves from the bor-
ing routine by drag racing their vehicles. They
played marathon card games. Arsonists burned
down an old building inside the Army Depot
while guards on the night
shift played poker.
Sometimes people try to
make the boredom more
palatable by drinking or
taking drugs. In 1987 it
was reported “Congressio-
nal committees, watchdog
groups and the [Nuclear Regulatory] commis-
sion have repeatedly found operators of nuclear
plants asleep or impaired by alcohol and
drugs.” Attempting to explain such behavior, a
representative of the Atomic Industrial Forum (the
industry lobbying group) said, “The problem is
that it’s an extremely boring job. It takes a great
deal of training. Then you sit there for hours and
hours and take an occasional meter reading”.
An American sailor who served as helmsman on
the nuclear aircraft carrier Independence dur-
ing the late 1970s/early 1980s claimed that he
used LSD almost every day on duty. He said it
was the only way to get through eight hours of
extremely boring work.
Stress
Working with dangerous technologies can also
be very stressful. We know that sustained high
levels of stress can lead to serious physical prob-
lems, such as a compromised immune system,
and serious emotional problems, such as severe
depression and even post-traumatic stress disor-
der (PTSD). PTSD includes difficulty concentrat-
ing, extreme suspicion of others, recurrent night-
mares and emotional detachment, all of which
tend to reduce reliability. At least 500,000 of
the 3.5 million American soldiers who served in
Vietnam have been diagnosed as suffering from
PTSD, as many as 30% of them may never lead
a normal life without medication and/or therapy.
As of 2008, there were at least 121 cases of
troubled Iraq/Afghanistan veterans charged
with committing homicide after they returned to
the U.S. . In August 2009, the New York Times
reported “the number of suicides reported by the
Army has risen to the highest level since record-
keeping began three decades ago.”
Stress also appears to increase so-called “ironic
errors”. Writing in Science magazine in 2009,
Harvard psychologist Daniel Wegner defined
an ironic error as “when we manage to do the
worse possible thing, the blunder so outrageous
that we think about it in advance and resolve
not to let that happen.... [M]
ental...monitoring processes
increase the likelihood of
such errors when we attempt
to exert control under mental
load”, such as when we are
under severe stress.
Drug and Alcohol Abuse
Boredom and stress can lead to drug and alco-
hol abuse. Data released by the Pentagon for
the years 1975-1990 show that almost 20,000
American military personnel were permanently
removed from nuclear duty over that period as a
result of drug abuse. Alcohol abuse added about
another 7000 to the total.
Disrupting the Biological Clock
Many of those who deal with nuclear weapons
must staff all critical duty stations throughout the
24-hour day, every day. That kind of round the
clock shift work inevitably plays havoc with the
biological clock. There appears to be an under-
lying body time rhythm that reaches its lowest
levels at night, regardless of sleep/wake sched-
ules. Thus, night shift workers inherently tend to
perform less well than day shift workers. Swed-
ish studies showed that the normal performance
of night shift workers was similar to that of day
shift workers who had lost an entire night’s
sleep. Rotating the work schedules of shift work-
ers both aggravates the problem and spreads it
to the day shift.
The Fallibility of Groups
One common strategy for assuring that an un-
reliable individual cannot cause a disaster in
the nuclear military is to require that a group
act together to, say, launch a missile attack.
But sometimes groups can be less reliable than
individuals.
In bureaucracies, the flow of information from
subordinates to superiors is often distorted. One
classic example is the “good news” syndrome:
subordinates edit problems out of the information
“Congressional committees,
watchdog groups and the [Nucle-
ar Regulatory] commission have
repeatedly found operators of
nuclear plants asleep or impaired
by alcohol and drugs.”
they send to higher management in order to pass
along a more pleasant picture. The result of all
this good news is that top-level decision makers
have a very distorted picture of what is really go-
ing on. And this problem tends to get worse, not
better, when there is more at stake, as in organi-
zations dealing with dangerous technologies.
“Groupthink” occurs when the quality of deci-
sions made by a group deteriorates as a result
of the pressure to maintain consensus among
its members. Increasingly isolating themselves
from other points of view, group members can
develop an illusion of invulnerability that sets
the stage for very risky decision making. For
example, during the Korean War, after the North
Koreans had been successfully driven out of the
South by US-led UN forces --- the original goal
of the war --- groupthink was involved in the US
decision to press on and invade North Korea.
Even though the Chinese threatened to enter the
war if North Korea were invaded, and every
member of the key American decision group
believed that Chinese entry would be a disaster,
they somehow managed to convince themselves
that the Chinese would never challenge the US.
They decided to invade. That drew the Chinese
into the war, as they had warned. They over-
whelmed American forces and drove deep into
South Korea. Years of fighting followed to regain
the ground lost. That reckless, foolish decision
cost of millions of lives.
It seems that the relatively easy U.S. victory over
the Taliban in Afghanistan encouraged the same
kind of arrogant over-optimism in the Bush ad-
ministration, and led us into the same self-made
trap in Iraq. Based on the misinformation that
Iraq was actively developing nuclear weapons,
that war has proved a terrible mistake, disas-
trous expensive in both blood and treasure.
Group psychosis is a situation in which a crazy
but charismatic leader is able to draw the other-
wise sane members of a group into his/her own
delusional worldview by isolating them and con-
trolling the conditions in which they live. Twen-
tieth century examples include the Reverend Jim
Jones and his followers at Jonestown, Guyana
in the 1970s and David Koresh and the Branch
Davidian at Waco, Texas in the early 1990s.
Suppose a charismatic military commander, who
seemed fully functional, had become deeply
disturbed. With great control over the lives of
troops already primed for obedience by the very
nature of military life, such a commander might
be able to draw them into his/her delusional
world. The crew of a nuclear missile submarine
is isolated for months at a time. The captain
has nearly complete control of the conditions in
which they live and work. And every nuclear
missile submarine carries enough firepower on
board to devastate any nation on earth.
In short, relying on groups does not fix the hu-
man reliability problem.
Nuclear War by Accident
In January 1987, the Indian Army prepared for
a major military exercise near the bordering
Pakistani province of Sind. Because Sind was
a stronghold of secessionist sentiment, Pakistan
concluded that India might be getting ready to
attack and moved its own forces to the border.
The two nations had already fought three wars
with each other since 1947. Both of them were
now nuclear-capable: India had successfully
tested a nuclear explosive device more than a
decade earlier; Pakistan was widely suspected
of having clandestine nuclear weapons. The
buildup of forces continued until nearly one mil-
lion Indian and Pakistani troops tensely faced
each other across the border. The threat of
nuclear war hung in the air as they waited for
the fighting to begin. Then,
after intense diplomatic ef-
forts, the confusion and mis-
communication induced by
human error began to clear
and the crisis was finally
defused. India and Pakistan
had almost blundered into a
catastrophic war by acci-
dent.
With both India and Paki-
stan armed with nuclear
weapons, during the 1999
Kargil war over Kashmir,
Pakistan reportedly got its
intermediate-range missiles
ready for nuclear attack and
“High level officials in both
countries issued at least a
dozen nuclear threats”. In
the midst of an active mili-
tary conflict between two
long-term rivals with both sides actively threaten-
ing each other with nuclear attack, it would not
take all that much miscommunication, misinter-
pretation, systems failure or simple human error
for the conventional conflict to escalate out of
control and unintentionally precipitate an acci-
dental nuclear war. According to an American
intelligence assessment completed in May 2002
--- as tensions between India and Pakistan once
again intensified --- whatever its cause, “a full-
scale nuclear exchange between the two rivals
could kill up to 12 million people immediately
and injure up to 7 million”. By 2010, both na-
tions have made great progress in developing
their nuclear arsenals, and little or no progress
in resolving the tensions that have repeatedly
brought them so close to accidental disaster.
Pakistan and India share a border with China
(some of it, in the region of Kashmir). China has
a much larger nuclear arsenal. Aside from the
catastrophic loss of life that would result from a
nuclear war between India and Pakistan, if one
or more of their nuclear-armed missiles acciden-
tally landed in China, the world could be drawn
into a much larger conflagration. And the whole
chain of events could easily be set in motion by
human error.
Is this an exaggeration? Do we have any real
evidence that a disastrous war can actually be
started by mistake? Think
back to 1914. Two alliances
of nations were locked in an
arms race, faced off against
each other in Europe. Both
sides were armed to the
teeth and convinced that
peace would be maintained
by the balance of power
they had achieved, despite
the growing tensions.
Then on June 28, 1914,
Archduke Ferdinand of Aus-
tria-Hungary and his wife
were assassinated by a Ser-
bian nationalist. The assassi-
nation set in motion a chain
of events that rapidly ran
out of the control of Europe’s
politicians and triggered a
war that no one wanted. By
the time it was over, 9 to 11
million people had lost their lives. Yet the whole
thing might have been prevented, but for a
simple failure of communications. The Kaiser had
sent the order that would have stopped the open-
ing attack of World War I (the German invasion
of Luxembourg on August 3, 1914) before it was
to begin. But the message arrived 30 minutes
late. In a classic understatement, the messengers
who finally delivered the belated order said, “a
mistake has been made.”
For an accidental nuclear war to occur there
has to be a triggering event. During the nuclear
age, there have been many serious false warn-
ings of nuclear attack that could have played a
key role in unleashing nuclear forces by mistake.
For example, in 1995, Russian warning radars
detected a rocket rising from the Norwegian Sea
that appeared to be a U.S. submarine-launched
Trident missile targeted at Moscow. The warn-
ing was relayed all the way up to President
Yeltsin, who had only a few minutes to decide
whether to launch a nuclear attack in response.
Fortunately, the Russian military determined that
they had made an error in projecting the mis-
sile’s trajectory. It was headed far out to sea, not
targeted on Moscow. The rocket was American,
but it was not Trident missile. It was a scientific
probe designed to study the Northern Lights. The
Russian government had been told of the launch,
but apparently ”a mistake had been made”, and
word never reached key military commanders.
It is widely assumed that with the end of the
Cold War and the disappearance of the “Soviet
threat”, Russian and American missiles were
taken off hair-trigger
alert and no longer
configured for launch-on-
warning of attack. But
that is simply not true.
Testifying before Con-
gress on July 18, 2007 --- sixteen years after the
demise of the Soviet Union --- former Secretary of
Defense William J. Perry said, “Both American
and Russian missiles remain in a launch-on-warn-
ing mode”. Perry then added, “And the inherent
danger of this status is aggravated by the fact
that the Russian warning system has deteriorated
since the ending of the Cold War.” In August
2007, “Russia declared... that it would begin
regularly sending its strategic bombers within
striking distance of the United States and allied
nations for the first time since the end of the
Cold War”. Since that time, Russian bombers
have been intercepted by British and Norwegian
fighter jets in NATO airspace, by Danish fight-
ers close to Danish airspace, and repeatedly by
U.S. and Canadian fighters as they approached
North America.
During a time of confrontation and crisis, a
weapons accident that resulted in a nuclear
explosion on the territory of a nuclear-armed
country or its allies could trigger an accidental
nuclear war. It is even possible that an accident
involving the weapons of friendly forces might
be surrounded in fog long enough to be misread
as an enemy attack. But a weapons accident
does not have to involve a nuclear explosion to
trigger nuclear war.
In my new book, The Technology Trap, which
will be published next month by Praeger/ABC-
CLIO, I list 100 publicly reported major nuclear
weapons-related accidents that occurred over the
period from 1950-2009 --- an average of one al-
most every 7 months for 60 years. They involve
the nuclear forces of the U.S., Russia, France
and Britain. In a number of these accidents, the
powerful conventional explosive in one or more
nuclear weapons was detonated. Suppose one
of these bombs had fallen into a nuclear weap-
ons or nuclear waste storage area, the huge
explosion and high levels of radioactivity that
would result could easily be misinterpreted as
an act of enemy sabotage or a deliberate attack
--- especially under the pressure and confusion
of a crisis. Such incidents appear in the public
record: in the summer of
1956, a B-47 bomber
crashed into a storage
igloo containing three
nuclear weapons in Eng-
land; on June 24, 1994,
a B-52 bomber crashed as the pilot pulled the
plane into a fatal stalling turn in a successful last
minute attempt to avoid crashing into a nuclear
weapons storage area.
It is also possible that a sufficiently deadly ter-
rorist attack could trigger an accidental nuclear
war. A terrorist attack with nuclear weapons on
the soil of a nuclear weapons state might lead to
a military counterattack involving nuclear weap-
ons against a country that that state supposed or
assumed had aided or encouraged the terrorists
---even if they had not. Could terrorists actually
launch such an attack?
The Terrorism of Mass Destruction
There are two basic ways that terrorists might
carry out an act of truly mass destruction. One
is to use a weapon of mass destruction that
they have built, bought or stolen; the other is to
stage a conventional terrorist bombing of a toxic
chemical plant, a nuclear power plant, or a toxic
chemical or nuclear waste storage area.
All the information necessary to design nuclear
bomb has been available in the public literature
for decades. More than 30 years ago, two un-
dergraduate students --- one at Princeton, one at
MIT --- independently designed workable nuclear
weapons using only publicly available sources.
In 1996, Time magazine reported that 17 sci-
entists at Los Alamos nuclear weapons labs had
been given the assignment of designing AND
building terrorist-type nuclear weapons using
“technology found on the shelves of Radio Shack
When the plane crashed it was head-
ed toward, and only about 120 miles
(about 15 minutes flying time) from the
Three Mile Island nuclear power plant.
[a typical consumer electronic store] and the
type of nuclear fuel sold on the black market”.
They successfully assembled more than a dozen
“homemade” nuclear bombs.
Terrorists might also be able to steal --- or buy ---
a well-designed, ready-made weapon. In 1997,
on American television, Russian General Alexan-
der Lebed claimed that Russia had lost track of
some 100 “suitcase” nuclear bombs.
If the terrorists who bombed New York’s World
Trade Center with airliners had used even a
crude, inefficient nuclear weapon instead, the
death toll would not have been in the thousands,
it would have been in the tens or hundreds of
thousands.
What about conventional attacks against nuclear
facilities? In early 2002, the U.S. reported that it
had found diagrams of nuclear power plants in
suspected terrorist hideouts in Afghanistan.
We may have already had a very close call. The
fourth jetliner, the Boeing 767 that crashed near
Somerset, Pennsylvania during the barrage of
hijackings on September 11, flew out of the East
Coast headed west and slightly south. After it
was hijacked, it looped around and headed east
again, and apparently went down when the pas-
sengers and crew fought the hijackers. When the
plane crashed it was headed toward, and only
about 120 miles (about 15 minutes flying time)
from the Three Mile Island nuclear power plant.
The Nuclear Regulatory Commission has admit-
ted that the containments of American nuclear
power plants were not designed to withstand the
impact of a 767 flying at 500 mph. If the plane
had reached and crashed into the nuclear reac-
tor building at Three Mile Island, we likely would
have had an American Chernobyl on our hands.
Conclusions
We humans are a very powerful and capable
species, but we are not perfect, and we never
will be. Our fallibility is part of what makes us
human, and like it or not, we must recognize that
it will always be with us. It sets inherent limits on
our ability to avoid error, even disastrous error.
There are also those among us who consider
the human life that physicians are trained so
carefully to preserve, to be just another commod-
ity, expendable in the quest for whatever goals
they seek. Perhaps someday we will find a way
to stop creating such people. But until that day
comes we must remove even the possibility that
they can acquire the means by which to do cata-
strophic damage to our species.
For both these reasons, we will never find peace
and security until we have rid the earth of nucle-
ar weapons. There is nothing they can do for us
that is anything as important as the damage they
will eventually do to us, by intention or by ac-
cident. We must get rid of them, the sooner the
better.
There are better ways to fight terrorism than with
massive military force; there are better ways to
find security than through the threat or use of
nuclear weapons. (I will be talking about one of
them in the plenary tomorrow morning). We are
such an adaptable species; there is little doubt
that we can learn to use them.
We can no more avoid the boundaries imposed
by our fallibility than we can revoke the laws of
nature. If we want to survive, let alone prosper,
we must learn to live within those boundaries.
There is no other choice.
The Human Factor
Safety and Nuclear Weapons
Christina Vigre Lundius MD
SLMK Sweden
IPPNW Congress - Basel 28th August 2010
At this very moment several thousand
warheads mounted on intercontinental
nuclear missiles are on
alert for delivery.
The safety of mankind
is ultimately
dependent on the vigilance and alertness
of a limited group of observers
monitoring perimeter radar systems.
LEVEL OF STIMULATION
MENTAL EFFICIENCY
HIGH
LOW
SEVERE UNDERSTIMULATION
UNDERSTIMULATION
OPTIMAL LEVEL OF STIMULATION
OVERSTIMULATION
SEVERE OVERSTIMULATION
Human errors
•
Airplane60-85% of incidents
and accidents
•
Chemical industry 80-90% of accidents
•
Off-shore79-90% of accidents
•
Nuclear power40-60% of incidents
and accidents
Under stimulation - Fatigue effects
•
Difficulty to concentrate
•
Hard to find a memory trace
•
More difficult to find a new strategy
•
More incoherent thought and speech
•
Lack of communication
Over stimulation - Mental stress
common in a crisis
•
Decreased flexibility and capability to
solve problems
•
Hasty decisions
•
Inability to make decisions
•
Impaired judgement, risk taking
Accidents and time of day
Biological clock
64564840322416
75
100
125
150
175
200
225
250
36.4
36.6
36.8
37.0
37.2
Time of day
Melatonin pM/min
Rectal temperature °C
temp
mel
160 8 160 160
Max
function
but
disturbed
sleep
Low
function
and
good
sleep
The causes of fatigue
•
Extended time awake
•
Monotony (incl. social isolation)
•
Low level lighting, infrasound, poor
oxygenation
•
Sleep disturbances
Sleepiness/fatigue and accidents
•
Increase with increasing length of the work shift
•
Accident rate increase threefold after 16h work.
•
Accidents have a probability of occurring in the
late night hours.
Night working and road accident risk
24211815129630
0
1
2
3
4
Heavy trucks, n=1.312
Time of day
Relative risk
24211815129630
0
5
10
15
20
Cars n=3.172
Time of day
Relative risk
all accidents
alcohol excluded
24211815129630
0
5
10
15
20
25
30
35
40
Single vehicle accidents - cars
Time of day
Relative risk
fatal
minor
Other factors that may increase risk
•
Alcohol and drugs
•
Physical/Psychiatric disease
•
Group thinking
•
Fear, paranoia e.g. of terrorism
Submarine admiral
“We often went submerged for a month or more.
Sometimes I could not leave the bridge
for more than a few hours in a week.
We were often provoked by American fighter
submarines.I kept awake on coffee and vodka.
I was often so tired so I could not discriminate
between red and green lights on the instrument panel.”
Prof. Lloyd Dumas:
”The difference between a trivial
error and a catastrophic error lies
not in the error itself, but in the
surrounding situation.”
References
Sweden:
•
Prof. T Åkerstedt, IPM, Karolinska Institute
•
Prof. T Theorell, IPM, Karolinska Institute
•
Prof. M Frankenheuser, Karolinska Institute
•
USA:
•
Prof. Lloyd Dumas, Univ.of Texas at Dallas
IPPNW/SLMK www.slmk.org