http://pec.lib.wvu.edu/record/P200301956-1960Hybrid corn.<p> Serial. Printed Ephemera Collection has: 1956:July 17, 1957:July 16, 1958:July 17, 1959:July 16, 1960:July 18.</p>West Virginia Cooperative Crop Reporting Service.Hybrid corn--West Virginia--Statistics--Periodicals.Hybrid corn--United States--Statistics--Periodicals.14256