G._B._Halsted--Christian_Felix_Klein

George Bruce Halsted (November 25, 1853 – March 16, 1922), usually cited as G. B. Halsted, was an American mathematician who explored foundations of geometry and introduced non-Euclidean geometry into the United States through his translations of works by Bolyai, Lobachevski, Saccheri, and Poincaré. He wrote an elementary geometry text, Rational Geometry, based on Hilbert's axioms, which was translated into French, German, and Japanese. Halsted produced original works in synthetic geometry, first with an elementary text in 1896, and with a text on synthetic projective geometry in 1906.