US Patent 4,820,737
United States Patent and Trademark Office
University of Iowa Research Foundation (Iowa City, IA, US)
Ophthalmic compositions useful as tear stimulants when topically applied to the eye for effective treatment of dry eye syndrome.
Schoenwald, Ronald D. and Barfknecht, Charles F. Lacrimal secretion stimulant (lss). US Patent 4,820,737 filed March 16, 1988 and issued April 11, 1989. https://ir.uiowa.edu/patents/66