Prince, Charles H. "Metal Working Shears." U. S. Patent number: US 1046852 A. Washington, DC: United States Patent and Trademark Office, 1912. http://www.uspto.gov/patft/index.html (1 April 2015).

Prince, Charles H. "Metal Working Shears." U. S. Patent number: US 1046852 A. Washington, DC: United States Patent and Trademark Office, 1912. http://www.uspto.gov/patft/index.html (1 April 2015).