"Last Rites" (Espionage Magazine, Apr. 1986): By Adam Hall. Quiller takes a vacation.
"Quiller" (The Great Detectives): This entry by Adam Hall is the definitive resource on Quiller. It includes a short forward by the editor, Otto Penzler.
"Why Spy?" (Espionage Magazine, Sept. 1987): Adam Hall explains why he writes Quiller novels.