Bingham, Richard D.
McGraw-Hill, 1991
Buku Teks
Holloway, William Vernon
McGraw-Hill , 1951
Buku Teks
Lancaster, Lane W.
Van Nostrand , 1952
Buku Teks
edited by Herbert L. Marx
H.W. Wilson, 1962
Buku Teks
Cox, George H.
Wadsworth/Thomson Learning, Belmont, CA, 2001
Buku Teks SO