wiki.creativecommons.org/wiki/Defining_Noncommercial
Defining “Noncommercial”: A Study of How the Online Population Understands “Noncommercial Use” was published September 14, 2009:
wiki.creativecommons.org/wiki/Frequently_Asked_Questions#Doe...
This links to the appropriate section in the Creative Commons Frequently Asked Questions page
mirrors.creativecommons.org/defining-noncommercial/Defining_...
Defining “Noncommercial” A Study of How the Online Population Understands “Noncommercial Use” report in a PDF from Creative Commons.
www.thehelpful.com/creativecommons/what-is-commercial-use.ht...
This is a small article setting out the non-commercial clause in the Creative Commons License.