"How to Help Someone who is Suicidal" (available from Mind Publications)

"Understanding Suicidal Behaviour" by Rory O'Connor and Noel Sheehy (British Psychological Society)

"Cry of Pain - Understanding Suicide and Self-Harm" by Mark Williams (Penguin)
Explains why suicide, often perceived to be a cry of help, is more usually a cry of pain.

"Suicide: The Tragedy of Hopelessness" by David Aldridge (LKP)