@misc{Ashley_George_Hall_(1866-1951)_Bulletin,
 author={Ashley, George Hall (1866-1951)},
 howpublished={online},
 publisher={Government Printing Office.},
 language={eng},
 type={czasopismo},
 title={Bulletin 641-L. Oil resources of Black Shales of the eastern United States},
 keywords={geologia, mineralogia, czasopisma, Stany Zjednoczone},
}