Beck, Anatole
Worth, 1970
Buku Teks
Richman, Fred, 1938-, author
Brooks/Cole, 1967
Buku Teks
Chartrand, Gary, author
Pearson Addison Wesley, 2008
Buku Teks
Batschelet, Edward
Springer-Verlag , 1975
Buku Teks
Rosen, Kenneth H., author
McGraw-Hill, 1999
Buku Teks