Abstract :
Comments to the paper by Albert W. Buel are presented by Robins Fleming, R.D. Coombs, George A. McKay, Schuyler B. Knox, Reginald A. Fessenden, and Jacob Feld. The author thanks all contributors to the discussion, especially for analytical and critical comments, which have helped to clear up some points and to direct attention to others that might have remained obscure.
