著者名,書名,版表示,出版者名,出版年,シリーズ名,番号,ISBN,ISSN,URL
"Catholic Church. Pope and Ewald, Paul and Hartmann, Ludo Moritz",Gregorii I papae Registrum epistolarum,,A. Weidmannos,1891,Monumenta Germaniae Historica,,,,https://cir.nii.ac.jp/crid/1130000796580790016