<http://schema.org/description>
"An analysis by Asymco\u2019s Horace Dediu has found that e-books are a strong component of Apple\u2019s sales, possibly generating about $1.3 billion in payments and grossing about $1.8 billion."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.cheatsheet.com/technology/how-big-is-apples-e-book-economy.html/>