foreword by Emrys Jones
Octopus Books, 1978
Buku Referensi
Pounds, Norman J. G., author
Silver Burdett, 1980
Buku Teks
edited by Otis W. Freeman and John W. Morris
McGraw-Hill, 1958
Buku Teks
edited by Otis W. Freeman and John W. Morris
McGraw-Hill, 1958
Buku Teks
Funk & Wagnalls, 2000,
Buku Referensi