The following book by Houston has a chapter which discusses, 'The PCP
pespective on alcohol and drug dependence': Houston, J (1998).  Making Sense
with Offenders. Wiley Chichester. 
The book edited by Button, E (1985). PCT and mental health, has 2 chapters
referred to in the book by Houston.
Not mentioned in Houston's book is:
Klion R (1993).  Chemical Dependency: a pct approach, in Leitner, L and
Dunnett N (eds).  Critical Issues in Personal Construct Psychotherapy.
Kreiger, Malabar.
This should get you started.  
regards,
Bob Green
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