"郑州市城市轨道交通近期建设规划(2014~2020 年)" [The Construction Plan of Zhengzhou Rapid Transit System (2014-2020)] (PDF) (in Chinese (China)). National Development and Reform Commission. Retrieved 2018-11-22.
"郑州地铁1号线二期和城郊铁路一期将开通试运营" [The Trial Operations of Zhengzhou Metro Line 1 (Phase II) and Chengjiao Line are Set to Start]. www.zhengzhou.gov.cn (in Chinese). Retrieved 2018-11-21.