Cinchona pubescens
- Images, description, and invasiveness.
- http://www.hear.org/pier/cipub.htm

Cinchona
- Brief encyclopedia article.
- http://www.encyclopedia.com/html/c1/cinchona.asp

Cinchona and its Product - Quinine
- Article with a brief description of the genus, its history of use, and cultivation.
- http://www.siu.edu/~ebl/leaflets/quinine.htm

Cinchona calisaya
- short description and medicinal uses
- http://www.botanical.com/botanical/mgmh/c/calisa08.html