Penrose, Roger
Society for Industrial and Applied Mathematics, 1987
eBooks
edited by Jean-Marie Henckaerts and Louise Doswald-Beck
Cambridge University Press, 2005
Buku Teks
Cambridge University Press, 2005
Buku Referensi
edited by Michael J. Collins
Academic Press, 1980
Buku Teks
Editor: A.J. Stockwell, R. Asthon
HMSO, 1995
Buku Teks