00271nam a22000857a 4500008004100000040005500041245001900096260005900115300001100174240726b        |||||||| |||| 00| 0 eng d  aNational Science LibrarycNational Science Library  aSbornik praci   aPraha: bVyzkumneho Ustavu Ekonomiky Hornictvi, c1972  a539p.