Bruner, Jerome S.
Harvard University Press, 1971
Buku Teks
Munk, Arthur W.
Abingdon Press, 1965
Buku Teks
Becker, Hellmut, author
Verlag Rombach, 1962
Buku Teks
Park, Joe
Macmillan, [date of publication not identified]
Buku Teks
Simon Rande, author
1985
UI - Skripsi (Membership)