*''The Psychology of Man's Possible Evolution'', [[P.D. Ouspensky]], [http://www.livingstonemusic.net/Psychology%20of%20Man's%20Possible%20Evolution.pdf Online Version] | *''The Psychology of Man's Possible Evolution'', [[P.D. Ouspensky]], [http://www.livingstonemusic.net/Psychology%20of%20Man's%20Possible%20Evolution.pdf Online Version] |