1 "Fișier:Elements_of_plane_and_spherical_trigonometry_(IA_elementsofplanes00newc).pdf".

Fișier:Elements of plane and spherical trigonometry (IA elementsofplanes00newc).pdf

PD-1923Public domain in the United States//commons.wikimedia.org/wiki/File:Elements_of_plane_and_spherical_trigonometry_(IA_elementsofplanes00newc).pdf...