Revocation how made
Chapter 2: Of the communication, acceptance and revocation of proposals
A proposal is revoked—
(1) by the communication of notice of revocation by the proposer to the other party;
(2) by the lapse of the time prescribed in such proposal for its acceptance, or, if no time is so prescribed, by the lapse of a reasonable time, without communication of the acceptance;
(3) by the failure of the acceptor to fulfil a condition precedent to acceptance; or
(4) by the death or insanity of the proposer, if the fact of his death or insanity comes to the knowledge of the acceptor before acceptance.
The Indian Contract Act, 1872 (Act No. 9 of 1872). From the updated text on India Code, with later amendments. Being checked against the official copy; amendment notes are not shown yet.