Cleveland, William L.
Westview Press , 2004
Buku Teks SO
Segui, william T
Thomson, 2007
Buku Teks SO
Schaaf, William L.
Wiley-Academy, 1965
Buku Teks SO
Volpe, Edmond L.
The Nooday Press , 1964
Koleksi Publik
Cary, William L.
The Foundation Press, 1970
Buku Teks