Section 39
Surety ship
Chapter 3: Parties to notes, bills and cheques
When the holder of an accepted bill of exchange enters into any contract with the acceptor which, under section 134 or 135 of the Indian Contract Act, 1872 (9 of 1872), would discharge the other parties, the holder may expressly reserve his right to charge the other parties, and in such case they are not discharged.
The Negotiable Instruments Act, 1881 (Act No. 26 of 1881). From the updated text on India Code, with later amendments. Being checked against the official copy; amendment notes are not shown yet.