Question: Don Barry Mason was the founder of the Psychedelic Shamanistic Institute (PSI), which other member that's Welsh, that died on 10 April 2016?

full_context: Document 1: Timothy Leary: Timothy Francis Leary (October 22, 1920 – May 31, 1996) was an American psychologist and writer known for advocating the exploration of the therapeutic potential of psychedelic drugs under controlled conditions. Leary conducted experiments under the Harvard Psilocybin Project during American legality of LSD and psilocybin, resulting in the Concord Prison Experiment and the Marsh Chapel Experiment. Leary's colleague, Richard Alpert (Ram Dass), was fired from Harvard University on May 27, 1963 for giving psilocybin to an undergraduate student. Leary was planning to leave Harvard when his teaching contract expired in June, the following month. He was fired, for "failure to keep classroom appointments", with his pay docked on April 30. National illumination as to the effects of psychedelics did not occur until after the Harvard scandal.
Document 2: Rick Strassman: Rick Strassman (born February 8, 1952 in Los Angeles, California) is a medical doctor specialized in psychiatry with a fellowship in clinical psychopharmacology research. He has held a fellowship in clinical psychopharmacology research at the University of California San Diego and was Professor of Psychiatry for eleven years at the University of New Mexico. After twenty years of intermission, Strassman was the first person in the United States to undertake human research with psychedelic, hallucinogenic, or entheogenic substances with his research on N,N-dimethyltryptamine. He is also the author of the well known book "DMT: The Spirit Molecule" which summarizes his academic research into DMT and includes his own reflections and conclusions based on this research.
Document 3: League for Spiritual Discovery: The League for Spiritual Discovery was a spiritual organization inspired by the works of Timothy Leary, and strove for legal use of lysergic acid diethylamide (LSD) for the purpose of meditation, insight, and spiritual understanding. It was in existence during the mid-to-late 1960s, and eventually closed by Leary. The New York Center for the League of Spiritual Discovery, in existence for around a year, was co-founded by Timothy Leary and Nina Graboi in 1966. The center was the first LSD-based meditation center in Manhattan.
Document 4: George Jung: George Jacob Jung (born August 6, 1942), nicknamed Boston George and El Americano, is a former drug trafficker and smuggler who was a major player in the cocaine trade in the United States in the 1970s and early 1980s. Jung was a part of the Medellín Cartel, which was responsible for up to 85 percent of the cocaine smuggled into the United States. He specialized in the smuggling of cocaine from Colombia on a large scale. His life story was portrayed in the biopic "Blow" (2001), starring Johnny Depp. Jung was released from prison on June 2, 2014, after serving nearly 20 years for drug-smuggling. On December 6, 2016 Jung was arrested and booked in Sacramento County jail for around a month, due to violating his parole. He was arrested while giving a speech in San Diego.
Document 5: Institute of Noetic Sciences: The Institute of Noetic Sciences (IONS) is an American non-profit parapsychological research institute. It was co-founded in 1973 by former astronaut Edgar Mitchell, along with investor Paul N. Temple, and others interested in purported paranormal phenomena, in order to encourage and conduct research on noetic theory and human potentials.
Document 6: Psychedelic music: Psychedelic music (sometimes psychedelia) covers a wide range of popular music styles and genres influenced by 1960s psychedelia, a subculture of people who used psychedelic drugs such as LSD, psilocybin mushrooms, mescaline and DMT to experience visual and auditory hallucinations, synesthesia and altered states of consciousness. Psychedelic music may also aim to enhance the experience of using these drugs.
Document 7: Howard Marks: Dennis Howard Marks (13 August 1945 – 10 April 2016) was a Welsh drug smuggler and author who achieved notoriety as an international cannabis smuggler through high-profile court cases. At his peak he claimed to have been smuggling consignments of the drug as large as 30 tons, and was connected with groups as diverse as the CIA, the IRA, MI6, and the Mafia. He was eventually convicted by the American Drug Enforcement Administration and handed a 25-year sentence to be served at Terre Haute; he was released in April 1995 after serving seven years. Though he had up to 43 different aliases, he became known as "Mr Nice" after he bought a passport from convicted murderer Donald Nice. After his release from prison, he published a best-selling autobiography, "Mr Nice", and campaigned publicly for changes in drugs legislation.
Document 8: Walter Douglas: Walter Douglas (born 1961) is an alleged Scottish drug trafficker and organised crime figure, dubbed the Tartan Pimpernel by the press, who is reportedly one of the richest in the United Kingdom with an estimated worth of £20 million. He was allegedly wanted in at least three countries on drug trafficking and gun running charges as of 2003, and Douglas was reported to have had ties to numerous international criminal organisations in Europe and North America as the head of the Delta crime syndicate. But in fact nothing has ever been proved against Douglas. In October 2013 there were no longer any warrants out against him and he staunchly maintained his innocence to a British journalist
Document 9: Curtis Warren: Curtis Francis Warren (born 31 May 1963) is an English gangster, who as Britain's most notorious drugs trafficker was formerly Interpol's Target One, and once listed on the Sunday Times Rich List.
Document 10: &quot;Freeway&quot; Rick Ross: Ricky Donnell "Freeway Rick" Ross (born January 26, 1960) is an American author and convicted drug trafficker best known for the drug empire he established in Los Angeles, California, in the early to mid 1980s. He was sentenced to life in prison, though the sentence was shortened on appeal and Ross was released in 2009.
Document 11: Harvard Psilocybin Project: The Harvard Psilocybin Project was a series of experiments in psychology conducted by Dr. Timothy Leary and Dr. Richard Alpert. The founding board of the project consisted of Leary, Aldous Huxley, David McClelland (Leary's superior at Harvard University), Frank Barron, Ralph Metzner, and two graduate students who were working on a project with mescaline. The experiments began some time in 1960 and lasted until March 1962, when other professors in the Harvard Center for Research in Personality raised concerns about the legitimacy and safety of the experiments in an internal meeting.
Document 12: Frank Lucas (drug dealer): Frank Lucas (born September 9, 1930) is an American former drug trafficker, who operated in Harlem during the late 1960s and early 1970s. He was particularly known for cutting out middlemen in the drug trade and buying heroin directly from his source in the Golden Triangle. Lucas boasted that he smuggled heroin using the coffins of dead American servicemen, but this claim is denied by his South East Asian associate, Leslie "Ike" Atkinson. Rather than hide the drugs in the coffins, they were hidden in the pallets underneath as depicted in the 2007 feature film "American Gangster" in which he was played by Denzel Washington, although the film fictionalized elements of Lucas' life for dramatic effect.
Document 13: Barry Seal: Adler Berriman "Barry" Seal (July 16, 1939 – February 19, 1986) was an American airline pilot who became a major drug smuggler for the Medellín Cartel. When Seal was convicted of smuggling charges, he became an informant for the Drug Enforcement Administration and testified in several major drug trials. He was murdered in 1986 by contract killers hired by Pablo Escobar, head of the Medellín Cartel.
Document 14: Patrick Basham: Dr Patrick Basham is an adjunct scholar with the Cato Institute, and the founding Director (in 2006) of the Democracy Institute. Basham was previously the founding director of the Social Affairs Centre at the Canadian Fraser Institute, and formerly Senior Fellow at the Cato Institute. He has published a number of books and contributed articles to a range of major US newspapers.
Document 15: Don Barry Mason: Don 'Barry' Mason (1950–2006) was the founder of the Psychedelic Shamanistic Institute (PSI), a networking organisation that encouraged ethnobotany and scientific research into cannabis and other psychoactive plants while contributing substantially to the public debate about drug policy reform. Associates of PSI include: Mathew Atha, Colin Angus, Brian Barritt, Michael Carmichael, Fraser Clark, Paul Devereux, the late John Entwistle, Paul Flynn MP, Ben Ganly, Lee Harris, Mike Jay, Howard Marks, Dr John Marks, Jonathan Ott, Dr Russell Newcombe, Richard Rudgley and Youth.
ground_truth: Dennis Howard Marks