Lewin, Kurt, author
Tavistock publications LTD, 1952
Buku Teks
Hormann, Hans
Suhrkamp , 1978
Buku Teks
Staiger, Emil
Zurich : Atlantis Verlag, 1963
Buku Teks
Strinberg, August
Munchen Georg Muller 1920
Buku Teks
Sears, David O., author
Erlangga, 1991
Buku Teks