<http://schema.org/alternativeHeadline>
"With a majority of sounds being of birds, Macauley Library contains sounds representative of 9,000 species and has a total running time of over 7,500 hours."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.mnn.com/earth-matters/animals/stories/largest-animal-sound-archive-goes-digital>