De Haan, H. (1995). New developments improved oil recovery. The Geological Society.
Lua i Stíl Chicago (17ú heag.)De Haan, H.J. New Developments Improved Oil Recovery. London: The Geological Society, 1995.
Lua MLA (9ú heag.)De Haan, H.J. New Developments Improved Oil Recovery. The Geological Society, 1995.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.