Some Studies on Productivity Monitoring of Surface Coal Mining Industry in India http://127.0.0.1/xmlui/handle/123456789/2265 Fri, 17 Apr 2026 02:33:04 GMT 2026-04-17T02:33:04Z Some Studies on Productivity Monitoring of Surface Coal Mining Industry in India http://127.0.0.1/xmlui/handle/123456789/2266 Some Studies on Productivity Monitoring of Surface Coal Mining Industry in India Sarkar, Chinmoy Mon, 13 Oct 1997 00:00:00 GMT http://127.0.0.1/xmlui/handle/123456789/2266 1997-10-13T00:00:00Z