Ross, Janet, author
Harper & Row , 1965
Buku Teks
Casanave, Christine Pearson
Prentice-Hall, 1986
Buku Teks
Simanjuntak, Herpinus, author
Kesaint Blanc, 2010
Buku Teks
Robinson, Lois
Harper & Row , 1967
Buku Teks
O`Neill, Robert
Longman, 1990
Buku Teks