Mason, J.I., On the angles of a polygon, The Mathematical Gazette (The Mathematical Association), 1946, 30 (291): 237–238, JSTOR 3611229, doi:10.2307/3611229.
jstor.org
Mason, J.I., On the angles of a polygon, The Mathematical Gazette (The Mathematical Association), 1946, 30 (291): 237–238, JSTOR 3611229, doi:10.2307/3611229.