Henderson, I. F.
Harlow, England Longman Scientific and Technical
Buku Referensi
Henderson, I. F.
Longman, 1975
Buku Referensi
edited by Brian Sutton-Smith [and others]
Utah State University Press, 1999
Buku Referensi
Collin, Simon
McGraw-Hill, 1995
Buku Teks SO
Geddes-Brown, Leslie
Page One, 2000
Buku Referensi