Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI)
Nagura Toshinobu,On the sectional curvatures of R-spaces,Osaka Journal of Mathematics,0030-6126,"Osaka University and Osaka City University, Departments of Mathematics",1974,11,1,211-220,https://cir.nii.ac.jp/crid/1390853649740640896,https://doi.org/10.18910/12576