Wilber, Donald N.
Princeton University Press, 1955
Buku Teks
Wilber, Donald N.
Princeton University Press, 1958
Buku Teks
Frye, Richard N.
Henry Holt and Company, 1953
Buku Teks
Frye, Richard N.
Allen & Unwin , 1960
Buku Teks
Bidgool, 2008
Buku Referensi