Luther B Miller & Wilbur C. Moore 
Psychology of Loyalty [PDF ebook] 

In this book, the authors discuss the psychology of loyalty. Topics include the military and political psychology of loyalty; the problem of loyalty in greedy institutions; the communal psychology of loyalty to a place; an empirical pilot study of the relationship of social media brand community activity with on-line consumer behavior; and a review of retail shopping loyalty differences between men and women.