<a href="https://en.wikipedia.org/wiki/U.S._National_Geodetic_Survey" class="extiw" title="en:U.S. National Geodetic Survey">Coast &amp; Geodetic Survey</a> - 1807-1957 - 150th anniversary - 3-cent 1957 issue U.S. stamp. The flag of the Coast and Geodetic Survey is featured as stamp's vignette.
Bureau of Engraving and Printing. Designed by Harold E. MacEwen.
U.S. Postal Service; National Postal Museum: <a rel="nofollow" class="external text" href="http://arago.si.edu/category_2029410.html">Coast &amp; Geodetic Survey Issue</a>