If you pre-ordered a copy of the new book, Boas of the World, by Graham Reynolds and Robert Henderson it  should be in your hands soon.  The chapters are written by various authors in their fields, it is well illustrated with photos of the various species/subspecies in situ and the chapters are well organized.  This book is a very good bargain at the price listed in the below post (if you have not ordered your copy yet).  It belongs in every collector’s, student’s and academician’s library.