Question: Which air transport operations hub was commanded by the most recent serial killer profiled in the book Cold North Killers: Canadian Serial Murder?

full_context: Document 1: Levi Bellfield: Yusuf Rahim (born Levi Rabetts; 17 May 1968), formerly known as Levi Bellfield, is an English serial killer. He was convicted on 25 February 2008 of the murders of Marsha McDonnell and Amelie Delagrange and the attempted murder of Kate Sheedy, and sentenced to life imprisonment.
Document 2: Dennis Nilsen: Dennis Andrew Nilsen (born 23 November 1945) is a Scottish serial killer and necrophiliac, also known as the Muswell Hill Murderer and the Kindly Killer, who murdered at least 12 young men in a series of killings committed between 1978 and 1983 in London, England. Convicted of six counts of murder and two of attempted murder at the Old Bailey, Nilsen was sentenced to life imprisonment on 4 November 1983, with a recommendation that he serve a minimum of 25 years. He is currently incarcerated at HMP Full Sutton maximum security prison in Full Sutton in the East Riding of Yorkshire, England.
Document 3: Karla Homolka: Karla Leanne Homolka (born 4 May 1970), also known as Karla Leanne Teale and Leanne Bordelais, is a Canadian serial killer who, with her first husband Paul Bernardo, raped and murdered at least three minors. She attracted worldwide media attention when she was convicted of manslaughter following a plea bargain in the 1991 and 1992 rape-murders of two Ontario teenage girls, Leslie Mahaffy and Kristen French, as well as the rape and death of her sister Tammy.
Document 4: Female Serial Killers: Female Serial Killers: How and Why Women Become Monsters is a non-fiction true crime history by Peter Vronsky, a criminal justice historian. It surveys the history of female serial killers and female-perpetrated serial homicide, its culture, psychopathology, and its investigation from the Roman Empire to the mid-2000s.
Document 5: Paul Bernardo: Paul Kenneth Bernardo (born 27 August 1964), also known as Paul Jason Teale, is a Canadian serial killer and serial rapist. He is known for several rapes in the eastern Metropolitan Toronto city of Scarborough, and a series of highly publicized sexual assaults, tortures and murders committed with his wife, Karla Homolka.
Document 6: Serial killer: A serial killer is typically a person who murders three or more people, usually in service of abnormal psychological gratification, with the murders taking place over more than a month and including a significant break (a "cooling off period") between them. Different authorities apply different criteria when designating serial killers; while most set a threshold of three murders, others extend it to four or lessen it to two. The Federal Bureau of Investigation (FBI), for example, defines serial killing as "a series of two or more murders, committed as separate events, usually, but not always, by one offender acting alone".
Document 7: Cold North Killers: Canadian Serial Murder: Cold North Killers: Canadian Serial Murder is a 2012 Canadian non-fiction book written by Lee Mellor and published by Dundurn Press. It documents the lives of sixty Canadian serial killers, with the earliest being Edward H. Rulloff and the most recent being Russell Williams. The book uses Katherine Ramsland's interpretation of what constitutes a serial killer—someone who has killed at least two people on two separate occasions, and who attempted to or likely would have killed again—as outlined in her 2007 book "The Human Predator". "Cold North Killer's" own definition of what constitutes a Canadian serial killer includes both Canadians who committed murder abroad (such as Keith Hunter Jesperson and Gordon Stewart Northcott) and non-Canadians who committed murder in Canada (like William Dean Christenson and Earle Nelson).
Document 8: CFB Trenton: Canadian Forces Base Trenton (IATA: YTR, ICAO: CYTR) (also CFB Trenton) is a Canadian Forces base located within the city of Quinte West, Ontario. It is operated as an air force base by the Royal Canadian Air Force (RCAF) and is the hub for air transport operations in Canada and abroad. Its primary RCAF lodger unit is 8 Wing, commonly referred to as 8 Wing Trenton.
Document 9: 2011 royal tour of Canada: The 2011 royal tour of Canada by Prince William, Duke of Cambridge, and Catherine, Duchess of Cambridge, took place between 30 June and 8 July 2011. The tour saw the newlywed couple visit all of Canada's regions. It was the first such tour undertaken by the Duke and Duchess since their marriage two months prior, and the first duties the couple carried out as members of the Canadian Royal Family. The tour was followed by more than 1,300 accredited media. It included the first use of the Duke of Cambridge's royal standard for Canada, the first Canadian citizenship ceremony attended by royalty, Canada Day ceremonies attended by approximately 800,000 people, and many smaller events across the country.
Document 10: Ronald Turpin: On 11 December 1962 Ronald Turpin, 29, was one of the two last people to be executed in Canada. The other prisoner was Arthur Lucas who was executed alongside Turpin at the Toronto (Don) Jail. Turpin had been convicted of the murder of Metropolitan Toronto police officer Frederick Nash. Nash had pulled Turpin over for a broken taillight while the latter was fleeing a robbery. The method of execution was hanging, the only form of civilian capital punishment ever used within Canada, although the Canadian military employed execution by firing squad. In 1976, capital punishment for murder was removed from Canada's Criminal Code, although it remained in the National Defence Act until 1998.
Document 11: Charles Cullen: Charles Edmund Cullen (born February 22, 1960) is a former nurse who is the most prolific serial killer in New Jersey history and is suspected to be the most prolific serial killer in American history. He confessed to authorities that he killed up to 40 patients during the course of his 16-year nursing career. But in subsequent interviews with police, psychiatric professionals, and journalists Charles Graeber and Steve Kroft, it became clear that he had killed many more, whom he could not specifically remember by name, though he could often remember details of their case. Experts have estimated that Charles Cullen may ultimately be responsible for 400 deaths, which would make him the most prolific serial killer in American history.
Document 12: Russell Williams (criminal): David Russell Williams (born March 7, 1963) is an English-born Canadian, convicted murderer, rapist, and former Colonel in the Canadian Forces. From July 2009 until his arrest in February 2010, he commanded CFB Trenton, a hub for air transport operations in Canada and abroad and the country's largest military airbase. Williams was also a decorated military pilot who had flown Canadian Forces VIP aircraft for dignitaries such as Queen Elizabeth II, Prince Philip, and the Governor General and Prime Minister of Canada.
Document 13: Luka Magnotta: Luka Rocco Magnotta (born Eric Clinton Kirk Newman; July 24, 1982) is a Canadian murderer, convicted of killing and dismembering Lin Jun, a Chinese international student, before mailing Jun's hands and feet to elementary schools and federal political party offices. This act gained international notoriety. After a video depicting the murder was posted online in May 2012, Magnotta fled Canada, becoming the subject of an Interpol Red Notice and prompting an international manhunt. He was apprehended at an Internet café in Berlin while reading news about himself in June 2012. After eight days of deliberations, a jury convicted him of first-degree murder on December 23, 2014. He was previously sought by animal rights groups for allegedly uploading videos of himself killing kittens.
Document 14: Robert Pickton: Robert William "Willy" Pickton (born October 24, 1949) of Port Coquitlam, British Columbia, Canada, is a Canadian serial killer convicted in 2007 of the second-degree murders of six women. He was also charged with the deaths of an additional 20 women, many of them from Vancouver's Downtown Eastside; however, these charges were stayed by the Crown in 2010. In December 2007, he was sentenced to life in prison, with no possibility of parole for 25 years – the longest sentence then available for murder under Canadian law.
Document 15: List of serial killers by number of victims: A serial killer is a person who murders three or more people, in two or more separate events over a period of time, for primarily psychological reasons. There are gaps of time between the killings, which may range from a few hours to many years. This list shows serial killers from the 20th century to present day by number of victims. In many cases, the exact number of victims assigned to a serial killer is not known, and even if that person is convicted of a few, there can be the possibility that he/she killed many more.
ground_truth: CFB Trenton