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
"Donner, Klaus",Extension of positive operators and Korovkin theorems,,Springer-Verlag,1982,Lecture notes in mathematics,,"3540111832,0387111832",,https://cir.nii.ac.jp/crid/1130282273039580032