Barger, Harold
Rand McNally, 1964
Buku Teks
Meek, Paul
NY (33 Liberty St., New York 10045) : Federal Reserve Bank of New York, 1982
Buku Teks
Robertson, Ross M.
Harcourt, Brace & World, 1964
Buku Teks
edited by Harold F. Williamson
Prentice-Hall, 1951
Buku Teks
Davies, J. Kenneth, 1925-
J.B. Lippincott, 1970
Buku Teks