William Robert Cox (March 14, 1901 – July 7, 1988) was an American author. He was a prolific writer of short stories and Western and Mystery novels mainly for the pulp and paperback markets. He wrote under at least six pseudonyms: Willard d'Arcy, Mike Frederic, John Parkhill, Joel Reeve, Roger G. Spellman and Jonas Ward.
He was born in Peapack-Gladstone, New Jersey. According to his widow, Casey Collins Cox, he was writing his 81st novel, Cemetery Jones and the Tombstone Wars on the day of his death in 1988. He was 87. He was survived by his wife, Casey, and his stepson, Douglas Campbell. He was the "beloved husband of Midge, Lamar, Lee, Pat and Casey,"
^James L. Traylor (1991). "Cox, William R.". In Lesley Henderson. Twentieth-century crime and mystery writers. St. James Press. pp. 247–50. ISBN978-1-55862-031-5. Traylor attributes one story to Cox (writing "as Wayne Robbins") - 'The Thing in Search of a Body', in Dime Mystery - without explanation. It seems simpler to attribute that to Wayne Robbins.