Description
Eleonore and Robert Watrous were friends and students of Dr. de Lange. In 1994, they completed the compilation and editing of letters that he had sent to his worldwide practice and published a remarkable book, Principle and Practice, that presents these letters for all to read and enjoy.
They also compiled two soft cover volumes to share more of his writings. This volume (151 pages) presents all of the lectures written and delivered by Dr. de Lange over more than two decades.
