I ordered this on Amazon recently Feedback to follow.

Divorce Poison: Protecting the Parent-Child Bond from a Vindictive Ex (Paperback)
by Richard A. Warshak
Paperback: 320 pages
Publisher: Regan Books; Reprint edition (March 1, 2003)
ISBN-10: 0060934573
ISBN-13: 978-0060934576

To quote his CV on his site ( OK guilty of drinking the koolaide

Dr. Warshak is generally considered one of the world’s leading authorities on pathological alienation in children.

To date what has irritated me the most about PAS is the level of clearly rebutted criticism which continues to circulate and is frequently incorrectly held up as fact. Read the FLC PAS note to see some of the issues which have been clearly rebutted elsewhere to see what I am referring to, although I agree with the opinion in as much as PAS shouldn't be used as a large blunt instrument , i.e. cases should be investigated on the basics of the individual circumstances and not an overarching generalisation. ( my 2bob's for what it's worth
de_dad