Census of India, 1981: Bihar. Series 4. Controller of Publications – Bihar. (1981). p. 22. https://books.google.com/books?id=rbNHAAAAYAAJ&q=expert+contractor. "It was the existence of coal that first attracted the railway authority to extend the railways and with them came the Gujrati people as an expert railway contractor with an experience of railway construction work at Thana. They then met Raja of Jharia and purchased some having underneath wast wealth in shape of coal"
[1]The Jharia underground fire still raging first came to notice in November, 1930 with subsidance at Seth Khora Ramji's Khas Jharia Colliery(Page 159). He was told that Seth Khora Ramji, whose mines lay underneath Jharia, had chosen to live in his house, which also collapsed in subsidance(Page 160). "The politics of labour under late colonialism: workers, unions, and the state in Chota Nagpur, 1928–1939 by Dilip Simeon."
