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
"Blok, W. J",On the degree of incompleteness of modal logics and the covering relation in the lattice of modal logics,,"Department of Mathematics, University of Amsterdam",1978,Report,,,,https://cir.nii.ac.jp/crid/1130282268635265792