Seven Principle For Making a Marriage Work and The Relationship Cure by John Gottman

http://www.gottman.com/

Divorce Busting by Michelle Wenier-Davis

http://www.divorcebusting.com/

Love Between Equals: How Peer Marriage Really Works by Pepper Schwartz

http://www.drpepperschwartz.com/Relationships.asp

The Ergonomic Couple by Barbara  Wetzel

http://theergonomiccouple.com/The-Ergonomic-Couple-by-Barbara-Wetzel-ISBN-978-061-537-0613.htm