Jacobs, Marius
Springer-Verlag, 1981
Buku Teks
edited by F.B. Golley
Elsiver, 1983
Buku Referensi
Whitmore, T.C.
Clarendon Press, 1990
Buku Teks
Nichol, John
David & Charies, 1990
Buku Referensi
edited by Mark Collins ; foreword by David Attenborough
Oxford University Press, 1990
Buku Teks