Aram, John D.
Pitman Pub. , 1986
Buku Teks
Flynn, Nancy
American Management Association, 2006
eBooks
Steiner, George Albert, 1912-
Random House, 1972
Buku Teks
edited by Louis Henkin
Spectrum, 1961
Buku Teks
edited by Fiona Sim, Martin McKee
McGraw-Hill, 2011
Buku Teks