Universitas Indonesia, 1998
UI - Skripsi (Membership)
Causton, David R., author
Gadjah Mada University Press, 1993
Buku Teks
Rubinow, S. I., author
Society for Industrial and Applied Mathematics, 1973
eBooks
Riggs, Douglas Shepard
The Williams&Wilkins , 1963
Buku Teks
Raina S. Robeva
Elsevier, 2008
Buku Teks