Encyclopedia of Life Sciences

eLS (previously known as the Encyclopedia of Life Sciences) is a reference work that covers the life sciences; it is published by Wiley-Blackwell. 
As of June 2012, there were more than 4,800 article topics published in "eLS" online. "eLS" is updated monthly and over 400 articles are added to eLS each year.
"eLS" is available online and in a print edition. The online edition was launched in April 2001, with the print edition published in January 2002. Full access to eLS requires a subscription. Article abstracts, key concepts, figures and references are freely accessible.
At the end of 2004, "eLS" was acquired by Wiley-Blackwell from the Nature Publishing Group.