@misc{Richardson_George_Burr_(1872-1949)_Bulletin, author={Richardson, George Burr (1872-1949)}, howpublished={online}, publisher={Government Printing Office.}, language={eng}, title={Bulletin 829. Geology and coal, oil, and gas resources of the New Kensington Quadrangle, Pennsylvania}, type={czasopismo}, keywords={geologia, mineralogia, petrografia, węgiel, Pensylwania (Stany Zjednoczone ; stan)}, }