Encyclopedias, Almanacs, Transcripts, and Maps
- Relativity, General
- Relativity, General
- Relativity, Special
- Relativity, Special
- Relativity, Theory of
- Religion and Dietary Practices
- Religious Experience Research Centre
- Remains of the RMS Titanic Discovered
- Remipedes: Remipedia
- Remy, Nicolas (1530-1612)
- Renaissance Botanical and Zoological Gardens
- Renal Agenesis
- Renal failure due to hypertension
- Renal Failure Due to Hypertension
- Renal Nutrition
- René Alphonse Higonnet
- René Antoine Ferchault de Réaumur
- René Auguste Caillié
- René Descartes
- René Descartes