Hugh Skillen

• The Enigma symposium 1998
• Spies of the airwaves
• Enigma and its achilles heel
• Knowledge strengthens the arm
• The Enigma Symposium 1992
• The Enigma symposium 1997
• The rest of BSM
• Enigma symposium, 1994
• Four years of war-time wit and humour in the Royal Signals/ATS/Intelligence Corps
• The Enigma Symposium 1995
• The Y compendium