DIN 22020-1:1998-08 Investigations of raw material in hard-coal-mining - Microscopical examination of hard coal, coke and briquettes - Part 1: Terms, survey of processes and their applications
1998DIN 22020-1:1998-08 Investigations of raw material in hard-coal-mining - Microscopical examination of hard coal, coke and briquettes - Part 1: Terms, survey of processes and their applications
1998DIN 22020-1:1998 Investigations of raw material in hard-coal-mining - Microscopical examination of hard coal, coke and briquettes - Part 1: Terms, survey of processes and their applications