Niazi, Ghulam Haider Khan
Maaref, 1966
Buku Teks
Lemkau, Paul V.
McGraw-Hill Book Company, INC, 1955
Buku Teks
Wilner, Daniel M., author
Macmillan, 1973
Buku Teks
Michael T. Haneline, William C. Meeker, editor
Jones and Bartlett Learning, 2011
Buku Teks
Healely, Bernard J., author
Jossey-Bass, 2009
Buku Teks