<http://schema.org/about>
"The most influential artists behind music as we know it might not be Beethoven or the Beatles -- but rather, birds. For ages those feathered crooners have been belting out their unique songs and calls in genres reminiscent"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/natural-sciences/bird-sound-database-contains-67000-songs-and-calls.html>