Cavanagh, John F. and Paul A. Cavanagh. "Method for manufacturing wafers." U. S. Patent number: 4352831 A. Washington, DC: United States Patent and Trademark Office, 1982.

Cavanagh, John F. and Paul A. Cavanagh. "Method for manufacturing wafers." U. S. Patent number: 4352831 A. Washington, DC: United States Patent and Trademark Office, 1982.