Heckert, J. Brooks (Josiah Brooks), 1893-, author
Ronald Press, 1953
Buku Teks
Lang, Theodore, author
Ronald Press, 1944
Buku Teks
Simini, Joseph Peter
McGraw-Hill, 1978
Buku Teks
Longman, Donald R., author
Richard D. Irwin, 1955
Buku Teks
Usry, Milton F., author
South Western, 1988
Buku Teks