The A.N. Marquis, 1966
Buku Referensi
Gilbert, Dorothy B., author
R.R.Bowker, [date of publication not identified]
Buku Teks
Routledge, Taylor & Francis Group, 2007
Buku Referensi
Hazel, John, author
Routledge, 2000
Buku Teks
Hazel, John, author
Routledge, 2000
Buku Referensi