Who can initiate impeachment proceedings against the President of India?

According to Article 61 of the Indian Constitution, the impeachment of the President for 'violation of the Constitution' can be initiated by either House of Parliament [c1][c2]. The process begins when a charge is preferred by either the Lok Sabha or the Rajya Sabha [t1][t5]. For the proceedings to commence, the charges must be signed by at least one-fourth of the total membership of the initiating House, and a 14-day written notice must be provided to the President [c2][t7]. Once the initiating House passes the resolution by a majority of two-thirds of its total membership, the other House investigates the charges [c4][t5]. The President has the right to appear and be represented during such investigations [c1]. If the second House also sustains the charges with a two-thirds majority, the President stands removed from office from the date the resolution is passed [t6][t7].

Sources

1. [1] Introduction to the Constitution of India, D. D. Basu (26th ed.). > Chapter 11: The Union Executive > 1. The President and the Vice-Prelideat > p. 206
2. [2] Laxmikanth, M. Indian Polity. 7th ed., McGraw Hill. > Chapter 18: President > Impeachment of President > p. 190
3. [3] Indian Polity, M. Laxmikanth(7th ed.) > Chapter 18: President > Impeachment of President > p. 190
4. [4] https://ceoharyana.gov.in/Website/ELECTIONCOMMISSION/Images/fe7f343d-12bc-45e3-b3af-e6ffadf44be7.pdf