Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) OKAMOTO Ken-Ichi and TAKAHASHI Satoru,"A Safety System for Elevators(""Case Studies on Reliability, Maintainability and Safety-10 Years from the last Reliability Handbook Publication-"" Part 5 Maintenance, Safety and Management of Systems)",The Journal of Reliability Engineering Association of Japan,09192697,Reliability Engineering Association of Japan,2008,30,7,584-589,https://cir.nii.ac.jp/crid/1390001204452652160,https://doi.org/10.11348/reajshinrai.30.7_584