"The United States 1847 Issue: A Cover Census"-Alexander, Thomas J.
(The U.S. Philatelic Classics Society, 2002).
"Ten Cent 1847
Covers"-Hart, Creighton C. & McDonald, Susan M. (2nd ed, Aug,
1970).
"1847 Covers from Arkansas"-Hart, Creighton C., ed. - The
Classics, #51, December 1965.