- U.S. Coast and Geodetic Survey
- Digital Commonwealth
- Boston Public Library
- U.S. Coast Survey Office
Relief shown by hachures. Depths shown by contours and soundings. General map. Does not show military operations. Includes list of authorities. Compiled at the U.S. Coast Survey Office ; drawn by A. Lindenkohl ; H. Lindenkohl & Chs. G. Krebs, lith.
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