Kamke, E.
Dover, 1950
Buku Teks SO
Lay, Steven R., 1944-
John Wiley & Sons, 1982
Buku Teks
edited by A. Hajnal, R. Rado, Vera T. Sos
North-Holland, 1975
Buku Teks
edited by Gunter Asser, Jurgen Flachsmeyer, Willi Rinow
Web Deutscher der Wissenschaften, 1972
Buku Teks
Klir, George J.
Prentice-Hall, 1988
Buku Teks