Grebanier, Bernard D.N.
Barron`s Educational Series, INC, 1958
Buku Teks SO
Stephen, Leslie, 1832-1904
University Paperbacks, 1963
Buku Teks SO
edited by Raymond Hickey
Cambridge University Press, 2010
eBooks
Richetti, John
John Wiley & Sons, 2017
Buku Teks SO
Ward, A.C.
Longman, 1955
Buku Teks SO