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 "Mejlbo, Lars C.",On a theorem of von Neumann concerning un-bounded operators in Hilbert space,,"Aarhus universitet, Matematisk Institut",1968,Preprint series,,,,https://cir.nii.ac.jp/crid/1130292461037747624