On Nov 7, 2016, at 1:37 PM, George Carhart <[log in to unmask]> wrote:can anyone tell me the best way to find a list of copyright dates for world map projections developed in the 20th century.ThanksGeorge Carhart-----------------------------Dr. George S. Carhart, Ph.DHistorian of Cartographyand Early Modern EuropeAntiquarian Map ConsultantHistoric Research Consultant7 Lafayette StreetPortlandME, 04101USA(207) 766-1517