Lewis, William Arthur, 1915-, author
George Allen & Unwin, 1951
Buku Teks
Lewis, William Arthur, 1915-, author
Unwin University Books, 1970
Buku Teks
PWN-Polish Scientiic Publishers, 1968
Buku Teks
Sachs, Ignacy
Cambridge University Press , 1987
Buku Teks
Tinbergen, Jan, 1903-, author
McGraw-Hill, 1967
Buku Teks