Vaile, Roland S.
The Roland Press Company , 1952
Buku Teks
Warren, Roland L., author
The Free Press, 1965
Buku Teks
Stromberg, Roland N.
Prentice-Hall, 1997
Buku Teks
Martin, Mike W., 1946-, author
McGraw-Hill, 1983
Buku Teks
Flint, Roland
The Dial Press, 1983
Buku Teks