Nachbin, Leopoldo, author
D. Van Nostrand, 1965
Buku Teks
Universitas Katolik Parahiyangan, {s.a}
Majalah, Jurnal, Buletin
Hochstadt, Harry, author
John Wiley & Sons, 1973
Buku Teks
Wardiman
Hanindita, 1987
Buku Teks
Hutahaean, E., author
"Jakarta: Gramedia, 1980",
Buku Teks