Wicks-Nelson, Rita, author
Prentice-Hall, 1997
Buku Teks
Coleman, Margaret Cecil
Allyn and Bacon, 1992
Buku Teks
Gor`kiy, Aleksey Maksimovich, author
Foreign Languages Publishing House, 1954
Buku Teks
Bakwin, Harry
Saunders, 1972
Buku Teks
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