Romeril, John, 1945-, author
Currency Press, 1975
Buku Teks
Garden City Books, [date of publication not identified]
Buku Referensi
Snyder, Houis L.
Princeton University Press, 1964
Buku Teks
Mende, Tibor
The Noonday Press, 1953
Buku Teks
Keyfitz, Nathan, author
The University of Chicago Press, 1968
Buku Teks