http://lawmin.nic.in/ld/subord/cer1.htm
CONDUCT OF ELECTIONS RULES, 1961
(Statutory Rules and Order)
1[CHAPTER II]
VOTING BY ELECTRONIC VOTING MACHINES
49-O. Elector deciding not to vote.-If an elector, after his
electoral roll number has been duly entered in the register of voters
in Form-17A and has put his signature or thumb impression thereon as
required under sub-rule (1) of rule 49L, decided not to record his
vote, a remark to this effect shall be made against the said entry in
Form 17A by the presiding officer and the signature or thumb
impression of the elector shall be obtained against such remark.