Beals, Ralph L., author
Macmillan, 1977
Buku Teks
Beals, Ralph L., author
Macmillan, 1959
Buku Teks
edited by Carleton S. Coon and Edward E. Hunt
Grosset & Dunlap, 1963
Buku Teks
edited by Susan Wright
Routledge, 1999
Buku Teks
edited by Teresa del Valle
Routledge, 1993
Buku Teks