Artikel Jurnal
Negoita, Constantin Virgil, author
The Benjamin Cumming Pub., 1985
Buku Teks
Maus, Rex., editor
McGraw-Hill, 1991
Buku Referensi
Shafer, Glenn, author
Society for Industrial and Applied Mathematics, 1996
eBooks
Keravnou, E. T., author
McGraw-Hill, 1986
Buku Teks