Clark, Mary E.
W.B. Saunders, 1973
Buku Teks
Simpson, George Gaylord
Harcourt Brace & World, 1964
Buku Teks SO
Pattee, Howard Hunt
[Springer, ], 2012
eBooks
Enger, Eldon D.
McGraw-Hill, 2003
Buku Referensi
edited by Jon Greenberg
Everyday Learning, 2001
Buku Teks