http://www.mid-day.com/columnists/2013/may/070513-diplomacy-cracks-china-in-ladakh.htm

That India doesn’t officially know the Chinese version of the LAC lies at the heart of the problem. Despite repeated requests from New Delhi since December 1981, when the first round of boundary talks took place, China has refused to spell out its perception of the LAC. This has allowed China to increase its territorial claims while frequently changing its patrolling patterns. India has to emphasise Article 10 of the 1996 agreement on ‘CBMs in the Military Field along the LAC’, where “the two sides agree(d) to speed up the process of clarification and confirmation of the Line of Actual Control.” To prevent another Depchang like crisis, India must ensure both countries exchange maps duly marked with their respective versions of the LAC.