Konopka, Gisela
Prentice-Hall, 1963
Buku Teks
Batten,T.R.
Oxford University Press, 1978
Buku Teks
Miles, Matthew B.
Teachers College Press, 1973
Buku Teks SO
Thibaut, John W.
John Wiley and Sons, 1967
Buku Teks SO
edited by Walter A. Friedlander
Prentice-Hall of India, 1977
Buku Teks