<http://schema.org/alternativeHeadline>
"Take a look at what the world's water supply would look like as a single drop - and find out what your family can do to protect it."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.mnn.com/green-tech/research-innovations/blogs/all-the-worlds-water-in-a-single-drop>