Barbu, Viorel
Academic Press, 1993
Buku Teks
Lions, J.L.
Society for Industrial and Applied Mathematics, 1972
eBooks
Chukwu, E.N.
Academic Press, 1992
Buku Teks
Akulenko, Leonid D.
Kluwer, 1994
Buku Teks
Whittle, Peter
John Wiley & Sons, 1990
Buku Teks