ブルーリボン賞・ローレル賞 選定車両一覧 [Blue Ribbon & Laurel Prize Winners List]. jrc.gr.jp (in Japanese). Japan: Japan Railfan Club. 29 May 2012. Archived from the original on 26 October 2010. Retrieved 9 January 2013.
railf.jp
"おおさか東線で221系の運用開始" [221 series starts operation on the Osaka Higashi Line]. Japan Railfan Magazine Online (in Japanese). Japan: Koyusha Co., Ltd. 12 March 2022. Retrieved 12 March 2022.
221系リニューアル車が営業運転を開始 [Refurbished 221 series in revenue service]. Japan Railfan Magazine Online (in Japanese). Japan: Koyusha Co., Ltd. 13 January 2013. Retrieved 13 January 2013.
web.archive.org
ブルーリボン賞・ローレル賞 選定車両一覧 [Blue Ribbon & Laurel Prize Winners List]. jrc.gr.jp (in Japanese). Japan: Japan Railfan Club. 29 May 2012. Archived from the original on 26 October 2010. Retrieved 9 January 2013.
westjr.co.jp
221系近郊型電車のリニューアルについて [221 series outer-suburban EMU refurbishment] (Press release) (in Japanese). West Japan Railway Company. 8 January 2013. Retrieved 8 January 2013.
