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
"Engel, Konrad and Gronau, Hans-Dietrich O. F.",Sperner theory in partially ordered sets,,BSB B. G. Teubner Verlagsgesellschaft,1985,Teubner-Texte zur Mathematik,,,,https://cir.nii.ac.jp/crid/1130000795691747456