[en] [Gutenberg 19058] • Ordnance Instructions for the United States Navy. / 1866. Fourth edition. Public Domain Books
[en] [Gutenberg 115] • United States Census Figures Back to 1630 HardPress
[en] [Gutenberg 37] • The 1990 United States Census [2nd] Xlibris Corporation
[en] [Gutenberg 29] • The 1990 United States Census HardPress