Plastics piping systems – Glass-reinforced thermosetting plastics (GRP) based on unsaturated polyester resin (UP) – Guidance for the structural analysis of buried GRP-UP pipelines; German version CEN/TS 14807:2013
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 03/01/2014

Plastics piping systems – Glass-reinforced thermosetting plastics (GRP) based on unsaturated polyester resin (UP) – Guidance for the structural analysis of buried GRP-UP pipelines; German version CEN/TS 14807:2004
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 01/01/2005