Groot, Gerard J.
Columbia University Press, 1951
Buku Teks SO
Christie, Agatha, 1890-1976
Gramedia Pustaka Utama, 2017
Buku Teks SO
edited by Eric Delson, Ian Tattersall, John A. Van Couvering and Alison S. Brokks
Garland Publishing, 2000
Buku Referensi
Richardson, W. Norman
Macmillan, 1976
Buku Teks
edited by Lori D. Hager
Routledge, 1997
Buku Teks