Lancaster, Lane W.
Van Nostrand , 1952
Buku Teks
Bingham, Richard D., author
McGraw-Hill, 1991
Buku Teks
Lane, Frederick S.
Martin's Press Inc., 1980
Buku Teks
Holloway, William Vernon, author
McGraw-Hill , 1951
Buku Teks
Zink, Harold, author
Macmillan, 1948
Buku Teks