@misc{Heald_Kenneth_Conrad_(1888-1971)_Bulletin, author={Heald, Kenneth Conrad (1888-1971)}, copyright={Biblioteka Politechniki GdaƄskiej}, howpublished={online}, publisher={Government Printing Office.}, language={eng}, type={czasopismo}, title={Bulletin 736. Contributions to economic geology : (short papers and preliminary reports). Part II, Mineral fuels}, keywords={geologia, mineralogia, petrografia, paliwa}, }