Goodyear Publishing, 1972
Buku Teks
Persell, Caroline Hodges, author
Harper & Row, 1984
Buku Teks
edited by Talcott Parsons
Voice of American, 1968
Buku Teks
Merrill, Francis E. (Francis Ellsworth), 1904-1969, author
Prentice-Hall, 1965
Buku Teks
edited by F.C. Bartlett
Kegan Paul, Trench, 1946
Buku Teks