Skinner, Brian J., author
John Wiley & Sons, 1987
Buku Teks
Gilluly, James, author
W.H. Freeman, 1959
Buku Teks
Billings, Marland P., author
Prentice-Hall, 1954
Buku Teks
Lange, Oktavii Konstantinovich, 1883-1975, author
Foreign Languages Publishing House , 196?
Buku Teks
Levorsen, A.I.
San Fransisco: W.H. Freeman, 1967
Buku Teks