#1 Gary R. Collins 1934- is the author of Effective Counseling. Proper LC heading is Collins, Gary R. (without a birth date) (LC 50026842) Most of his works can be found on the Gary R. Collins author page; however the two pages should not be combined due to the existence of other authors called Gary Collins, including
#2 Gary Collins 1938-, author of The Hour Magazine Cookbook. Proper LC heading is Collins, Gary, 1938-2012 (LC 85044362)
#3 Caldwell, Clay, pseudonym of George Davies.
#4 Collins, Gary, 1949- author of Where eagles lie fallen (LC 2010041166)