Wessel, C. (1999). On the analytical representation of direction: An attempt applied chiefly to solving plane and spherical polygons. The Royal Danish Academy of Sciences and Letters.
Lua i Stíl Chicago (17ú heag.)Wessel, Caspar. On the Analytical Representation of Direction: An Attempt Applied Chiefly to Solving Plane and Spherical Polygons. Copenhagen: The Royal Danish Academy of Sciences and Letters, 1999.
Lua MLA (9ú heag.)Wessel, Caspar. On the Analytical Representation of Direction: An Attempt Applied Chiefly to Solving Plane and Spherical Polygons. The Royal Danish Academy of Sciences and Letters, 1999.
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