"Copyright Terms & Definitions." The Copyright Society of the USA, www.csusa.org/page/Definitions.
Posner, R. "Why There Are Too Many Patents in America." The Atlantic, 12 July 2012, www.theatlantic.com/business/archive/2012/07/why-there-are-too-many-patents-in-america/259725.
"Protecting Your Trademark." United States Patent and Trademark Office, Sept. 2018, www.uspto.gov/sites/default/files/documents/BasicFacts.pdf.