@article{oai:air.repo.nii.ac.jp:00004107,
 author = {安藤, 英夫 and 鎌形, 利夫 and ANDO, Hideo and KAMAGATA, Toshio},
 journal = {秋田大学教育学部研究紀要 自然科学, Memoirs of the Faculty of Education, Akita University. Natural science},
 month = {Feb},
 pages = {8--17},
 title = {Remarks on the Lusternik-Schnirelmann category},
 volume = {21},
 year = {1971}
}