Higgins, Benjamin
D. Van Nostrand, 1963
Buku Teks SO
Higgins, Benjamin
Richard D. Irwin, 1962
Buku Teks
Doren, Carl van
World Publishing, 1948
Buku Teks SO
Walsh, Henry H.
The Stephen Press, 1969
Buku Teks SO
Penning, W.L.
S.L. Van Looy, [Date of publication not identified]
Buku Teks