Green, George S.
Holt, Rinehart and Winston, 1972
Buku Teks SO
Allen, W. Stannard, author
Longman, 1974
Buku Teks SO
Allen, W. Stannard, author
Longman, 1974
Buku Teks SO
V.S. Belevitskaya-Khalizeva ...[et al.]
Foreign Languages Publishing House, [date of publication not identified]
Buku Referensi
Shidle, Norman G., author
McGraw-Hill, 1951
Buku Teks