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 International Telegraph and Telephone Consultative Committee. Plenary Assembly and International Telecommunication Union and International Telegraph and Telephone Consultative Committee,Telephone transmission quality : series P recommendations,,International Telecommunication Union,1989,"Blue book : CCITT, IXth Plenary Assembly, Melbourne, 14-25 November 1988",,9261034411,,https://cir.nii.ac.jp/crid/1130000797226127104