Iowa State University Veterinarian Records, RS 22/6/0/9, University Archives, Special Collections Department, Iowa State University, http://www.add.lib.iastate.edu/spcl/arch/rgrp/22-6-0-9.html
The study of coumarin derivatives began with the identification of the causative agent in sweet clover responsible for the hemorrhagic disease of cattle now called "sweet clover disease." The investigation of this disease and the isolation of the etiological factor has established both the chemical and physiological properties of dicoumarin.
Iowa State University Veterinarian: Vol. 5
, Article 6.
Available at: http://lib.dr.iastate.edu/iowastate_veterinarian/vol5/iss4/6