Cite

Chart Of The North East Trade Winds [cartographic material] / National Observatory.

MLA

Chart Of The North East Trade Winds [Cartographic Material] / National Observatory. National Observatory, 1851. https://collections.library.yale.edu/catalog/15833022.

APA, 6th edition

Chart Of The North East Trade Winds [cartographic material] / National Observatory. (1851). [Nautical charts]. National Observatory, https://collections.library.yale.edu/catalog/15833022.