The Rocas islands and atoll. This is the only Atlantic atoll and was positioned
by Samuel Phillips Lee, commanding officer of the U.S. Surveying Brig DOLPHIN.
In: Report and Charts of the Cruise of the U.S. Surveying Brig DOLPHIN:
Samuel Phillips Lee, U.S. Navy. Commanding. Senate Executive Document No. 59.
33rd Congress, 1st Session.