Helen Schucman authorized the Foundation for Inner Peace to publish A Course in Miracles. She approved the version that they publish, working closely with Ken Wapnick and others to ensure that the material was clear and faithful to the scribing process. Earlier versions of the course have been published; it’s an ongoing source of conflict which edition one should read. The answer is actually easy: the version which helps you undo guilt and remember happiness. Helen was clear which version she felt met that standard.