Maxmillan Company, 1987
Buku Referensi
Maxmillan Company, 1987
Buku Referensi
Macmillan Publishing Company, 1987
Buku Referensi
edited by Vergilius Ferm
Littlefield, Adam and Co., 1959
Buku Referensi
edited by Vergilius Ferm
Philosophical Library, 1945
Buku Referensi