DIN 19565-5
DIN 19565-5 Prefabricated glass fibre reinforced plastic (UP-GF) manholes for use in sewerage systems; dimensions and technical delivery conditions
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 11/01/1990
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 11/01/1990