Proceedings of symposium on drilling technology and engineering aids to geoogical exploration calcutta 12th to 15th february 1980
Special publication
Proceedings of symposium on drilling technology and engineering aids to geoogical exploration calcutta 12th to 15th february 1980 Special publication No.4 - Newdelhi Geological Survey of India 1980
Proceedings of symposium on drilling technology and engineering aids to geoogical exploration calcutta 12th to 15th february 1980 Special publication No.4 - Newdelhi Geological Survey of India 1980