Sharma, Aman. Government promotes 28 IAS officers to secretary and special secretary ranks. India Today. New Delhi. 19 April 2012 [1 September 2017]. ISSN 0254-8399
Ministers of State. India Today. [2018-11-17]. (原始内容存档于2018-11-17) (英语). National Portal of India. Council of Ministers. www.india.gov.in. [2018-11-17]
下表以各邦及聯邦属地的英文名稱按字母排列: Retired IAS officer Utpal Kumar Singh appointed Secretary in Lok Sabha. The Republic World. 2020-11-30 [2021-01-04]. (原始内容存档于2020-09-19)
as PM’s private secretary. The Hindu. 2014-07-20 [2024-07-16] (英语). Sanjeev Kumar Singla appointed as the next Ambassador of India to the State of Israel