Four Eyed Fish
- Information of the fish having eyes raised above the top of the head and divided in two different parts. Physical description, habitat, special anatomical, physiological or behavioral adaptations.
- http://whozoo.org/Intro2000/rafajohn/RJ_FourEyedFish.html

Rivulus
- Information regarding the hermaphroditic fish Rivulus marmoratus.
- http://www.biol.vt.edu/faculty/turner/rivmar/

Killi-Data Online
- Aims to present all available information on the oviparous Cyprinodontiformes, also known as killies.
- http://www.killi-data.org/