Deborah M. Anapol, Polyamory: The New Love Without Limits

Dossie Easton, Catherine A. Liszt, The Ethical Slut: A Guide to Infinite Sexual Possibilities 

Barbara and Michael Foster, and Letha Hadady, Three in Love: Menages a Trois from Ancient to Modern Times

Lori Gammon and Bill Strong, Threesome: How To Fulfill Your Favorite Fantasy

Nena and George O'Neill, Open Marriage: A New Life Style for Couples
This was the first book to appear on the subject back in the 1970s.

Patti Thomas, Recreational Sex: An Insider's Guide to the Swinging Lifestyle
 

Copyright 1999 by Steve Vakesh