Abrams, Lynn, author
Roudledge, 2010
Buku Teks
Stumpf, Samuel Enoch, 1918-1998, author
McGraw-Hill, 2012
Buku Teks
Lewes, George Henry, author
Cambridge University Press, 2013
eBooks
Burns, Edward McNall, 1897-1972, author
W.W Norton, 1984
Buku Teks
Ibnu Khaldun, author
Routledge & Kegan Paul, 1958
Buku Teks