Dent, Borden D.
Wm. C. Brown , 1990
Buku Teks
edited by Barbara P. Buttenfield, Robert B. McMaster ; foreword by Herbert Freeman
Longman Scientific & Technical, 1991
Buku Teks
Raisz, Erwin Josephus, 1893-
McGraw-Hill, 1948
Buku Teks
Robinson, Arthur H.
John Wiley & Sons, 1978
Buku Teks
John Wiley & Sons, 1995
Buku Teks