THE REX COLE JR. DETECTIVE STORIES 
By Gordon Chapman
Grosset & Dunlap


  1. REX COLE JR., AND THE CRYSTAL CLUE
  2. REX COLE JR., AND THE GRINNING GHOST

Source:

Advertisement inside wrapper of The Bobbsey Twins at Snow Lodge, by Laura Lee Hope, Illustrated by ???. Grosset & Dunlap. New York. 1913