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
"Gregory I, Pope, ca. and Martyn, John R. C. and Pontifical Institute of Mediaeval Studies",The letters of Gregory the Great,,Pontifical Institute of Mediaeval Studies,2004,Mediaeval sources in translation,,0888442904,,https://cir.nii.ac.jp/crid/1130282271339950336