Hutagalung, Sophar Maru, author
Sinar Grafika, 2013
Buku Teks
Kunstler, William M.
Oceana Publications, Inc, 1963
Buku Teks
Merges, Robert Patrick, author
Michie, 1997
Buku Teks
Holmes Jr, Oliver Wendell
Little, Brown and Company, 1923
Buku Teks
Holmes, Oliver Wendell
Little, Brown & Co., 1951
Buku Klasik