Authors: R. (sorted by quantity of books)
- Boyle, Robert 1627-1691 2 books
- Ambedkar, B. R. (Bhimrao Ramji) 1891-1956 2 books
- Nettleship, Richard Lewis 1846-1892 2 books
- Nassau, Robert Hamill 1835-1921 2 books
- Burleigh, Sydney Richmond 1853-1931 2 books
- Tuker, M. A. R. (Mildred Anna Rosalie) - 2 books
- Hall, H. R. (Harry Reginald) 1873-1930 2 books
- Kloosterman, J. R. (Jan Ritskes) 1847-1914 2 books
- Campbell, R. J. (Reginald John) 1867-1956 2 books
- Effinger, John R. (John Robert) 1869-1933 2 books
- Haines, Charles Reginald - 2 books
- Mathews, R. H. (Robert Hamilton) 1841-1918 2 books
- Edmonds, Cyrus R. - 2 books
- Brown, Charles Reynolds 1862-1950 2 books
- James, H. R. (Henry Rosher) 1862-1931 2 books
- Martin, Helen Reimensnyder 1868-1939 2 books
- Wheelan, Albertine Randall - 2 books
- Mackenzie, R. Shelton (Robert Shelton) 1809-1880 2 books
- Barbiera, Raffaello 1851-1934 2 books
- Stockheker, R. W. (Ralph Walter) 1908-2004 2 books
- Menel, R. - 2 books
- Rose, R. Selden (Robert Selden) 1888-1964 2 books
- Seton-Watson, R. W. (Robert William) 1879-1951 2 books
- Wingate, F. R. (Francis Reginald), Sir 1861-1953 2 books
- Spofford, Ainsworth Rand 1825-1908 2 books