- http://en.wikipedia.org/wiki/Crab
- http://www.whateats.com/what-eats-a-crab
- http://animals.pawnation.com/aggression-hermit-crabs-1507.html
- http://icb.oxfordjournals.org/content/early/2011/08/19/icb.icr100.full#sec-4
- http://icb.oxfordjournals.org/content/8/3/673.abstract
- http://www.infoplease.com/dk/encyclopedia/crustaceans.html