Adams, James Truslow, author
1946
Buku Referensi
Cummings, Paul, author
St. Martin's Press, 1966
Buku Referensi
Plano, Jack C., author
Holt, Rinehart and Winston, 1985
Buku Referensi
edited by Edward Conrad Smith and Arnold John Zurcher
Barnes & Noble, 1966
Buku Teks
Mellinkoff, David, author
[Publisher not identified], 1992
Buku Teks