Teacher's key to Plane geometry, Welchons, A. M. (Alvie M.), 1894-1952. Krickenberger, William R., [from old catalog] joint author. Geometry, Plane. QA455 .W415 513 WEP Boston, New York [etc.] Ginn and company 1934. 1934. 1934 Text 269 p. : eng