Work Cited
https://gigaom.com/2007/08/16/how-the-physical-distribution-of-digital-goods-impacts-the-environment/
http://www.cnet.com/news/this-just-in-cds-are-a-lot-more-popular-than-lps/
http://www.riaa.com/faq.php
http://www.research.philips.com/technologies/projects/cd/