X151.2 Yer P Yerkes, Robert Mearns, 1876 A point scale for measuring mental ability. 1923 revision, bny Robert M. Yerkes... Baltimore, Warwick & York, inc., 1915. Coatores: James W. Bridges and Rose S. Hardwick. vii, 219 p. incl. plates. 22 cm. "Original edition...written by Robert M. Yaerkes, James W. Bridges and Rose S. Hardwick" "Point scale bibliography:" p.l 144-147.