Haanel, Charles F, author
Mind Power Corporation, 2006
Buku Teks
Collins, John E. (John Edward), author
Rowman & Littlefield, 1991
Buku Teks
Köhler, Wolfgang, 1887-1967, author
Liveright, 1947
Buku Teks
Bauer, Raymond A., author
Harvard University Press, 1952; 1959
Buku Teks
Westen, Drew, author
John Wiley & Sons Australia, 2006
Buku Teks