Encyclopedias, Almanacs, Transcripts, and Maps
- Roy J. Plunkett
- Royal Priest Research
- Rózsa Péter
- Rubinstein-Taybi syndrome
- Rubinstein-Taybi Syndrome
- Rudhyar, Dane (1895-1985)
- Rudolf Carl Virchow
- Rudolf Friedrich Alfred Clebsch
- Rudolf Julius Emmanuel Clausius
- Rudolf Ludwig Mossbauer
- Rudolf Magnus
- Rudolf Otto Sigismund Lipschitz
- Rudolph Albert von Kölliker
- Rudolph Diesel
- Rudolph Jacob Camerarius
- Ruggiero Guiseppe Boscovich
- Ruggles, A. D. (ca. 1853)
- Ruh Ve Madde (Journal)
- Ruhani Satsang
- Rule of Sixes