https://books.google.it/books?hl=it&lr=&id=nUdi-t8haWUC&oi=fnd&pg=PA685&dq=The+Swimming+Crabs+of+the+Genus+Callinectes+(Decapoda:+Portunidae)&ots=PAQVoId-xf&sig=DaVXElqRM7pVmjJvmNMLwaRn9pg&redir_esc=y#v=onepage&q=The%20Swimming%20Crabs%20of%20the%20Genus%20Callinectes%20(Decapoda%3A%20Portunidae)&f=false
https://www.fisheries.noaa.gov/species/blue-crab