Westrup, J. A.
William Collins Sons, 1959
Buku Referensi
Wade-Matthews, Max
Southwater, 2013
Buku Teks
Manzer, Ronald A.
McGraw-Hill Ryerson, 1974
Buku Teks
McInnis, Edgar
Holt, Rinehart and Winston of Canada, 1982
Buku Teks
edited by George W. Brown
University of California Press, 1954
Buku Teks