| The riddle of the rocks / 1895
Charles Egbert Craddock | |
| The Riddle of the Sands
Erskine Childers | |
| The Riddle of the Spinning Wheel
Mary E. Hanshew; Thomas W. Hanshew | |
| The Riddle of the Universe at the close of the nineteenth century
Ernst Haeckel | |
| The riddle of Three-Way Creek
Ridgwell Cullum | |
| The ride to the lady, and other poems
Helen Gray Cone | |
| The Rider in Khaki: A Novel
Nat Gould | |
| The Rider of Golden Bar
William Patterson White | |
| The Rider of the Mohave: A Western Story
James Fellom | |
| The Rider of Waroona
G. Firth Scott |
