Charles R. Pike is a pseudonym that three different authors wrote under. The pseudonym was only used to write the Jubal Cade series.
Terry Harknett wrote the first three in the series 1)The Killing Trail 2) Double Cross and 3) The Hungry Gun. After these three, Harknett passed the baton on to Angus Wells who wrote all the remaining books in the Jubal Cade series except one which was wrote by Kenneth Bulmer.