Maxwell, Robert L.
American Library Association, 2004
Buku Referensi
Atiyah, P.S.
Oxford University Press , 1987
Buku Teks
edited by Michael Gorman, Paul W. Winkler
American Library Association, 1978
Buku Referensi
Eder, Phanor J.
New York University press, 1950
Buku Teks
Arenson, J. T.
J.J. Groen & Zoon N.V., 1953
Buku Teks