Beach, Walter Edwards
Cambridge, Mass., Harvard University Press
Buku Teks SO
American Society for Testing materials, 1959
Buku Teks SO
Carter, April
Postwar World, 1945
Buku Teks SO
edited by Kare Ringlund, Ellen Mosleth, and Daryl J. Mares
Westview Press, 1990
Buku Referensi
by edited by Ronald W. Estabrook, James R. Gillette and Kenneth C. Leibman/
Williams & Wilkins, 1973
Buku Teks SO