Penning, W.L., author
S.L. Van Looy, [Date of publication not identified]
Buku Teks
Penning, W.L., author
S.L. Van Looy, 1920
Buku Teks
Doren, Carl van, author
World Publishing, 1948
Buku Teks
Walsh, Henry H., author
The Stephen Press, 1969
Buku Teks
Lewin, Benjamin
John Wiley & Sons, 1983
Buku Teks