http://www.bikeleague.org/resources/reports/report_economics.php
http://www.planetizen.com/taxonomy/term/2131
http://bicycling.com/blogs/roadrights/2010/07/07/adding-bicycle-infrastructure-creates-more-riders/
http://www.copenhagenize.com/2011/02/provincal-bicycle-infrastructure.html
http://streetsblog.net/2010/03/29/whats-so-scary-about-bicycle-infrastructure/
http://www.theurbancountry.com/2011/05/bicycle-infrastructure-is-good-for.html