Mumbai, Sept. 13 -- Canada's Brookfield Asset Management and Singapore's Temasek Holdings Ltd have joined the race to buy the gas pipeline assets of state-run GAIL (India) Ltd, three people aware of the matter said. A potential deal would be a vital win for Brookfield, which recently bought the gas pipeline assets of Reliance Industries Ltd. GAIL owns more than two-thirds of India's 12,000-km pipeline network. GAIL, which is in the process of divesting its pipeline business, has already received interest from state-run Indian Oil Corp. Ltd (IOCL) and Bharat Petroleum Corp. Ltd (BPCL) for the gas transmission assets. "Prospective bidders have begun initial discussions with GAIL and are expected to put a formal offer once a formal sale proces...