De Haan, H. (1995). New developments improved oil recovery. The Geological Society.
Chicago-viite (17. p.)De Haan, H.J. New Developments Improved Oil Recovery. London: The Geological Society, 1995.
MLA-viite (9. p.)De Haan, H.J. New Developments Improved Oil Recovery. The Geological Society, 1995.
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