7118
The two most common systems are the classification adopted by the website AmphibiaWeb , University of California , Berkeley and the classification by herpetologist Darrel Frost and the American Museum of Natural History , available as the online reference database " Amphibian Species of the World " .
 AmphibiaWeb, University of California, Berkeley, Darrel Frost, American Museum of Natural History
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 AmphibiaWeb, University of California, Berkeley, Darrel Frost, American Museum of Natural History