Sujeito
- Ancelet, G.1
- Anderson, Alexander, 1775-18702
- Anderson, James1
- Andrews, E. Wyllys (Edward Wyllys)1
- Andrews, Edmund1
- Anemia1
- Anesthesia5
- Angerer, Victor, 1839-18941
- Animal Husbandry1
- Antonia, Valeria1
- Arding, Bjorn1
- Arena, Jay M.1
- Arlt, Ferdinand, Ritter von, 1812-18871
- Armstrong, John1
- Arnaldus, de Villanova, -13111
- Arteries1
- Artwork6
- Aschoff, L. (Ludwig), 1866-19421
- Aselli, Gaspare, 1581-16262
- Ash, John1