Pipes of high-density polyethylene (PE-HD) for buried telecommunication – Dimensions and technical delivery conditions
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 08/01/2009

Pipes of high-density polyethylene (PE-HD) for buried telecommunication – Dimensions and technical delivery conditions
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 07/01/2012