Flanges and their joints - Circular flanges for pipes, valves, fittings and accessories, Class designated - Part 1: Steel flanges, NPS 1/2 to 24; German version EN 1759-1:2004— 78 стр.
Flanges and their joints - Circular flanges for pipes, valves, fittings and accessories - Part 1: Steel flanges, PN designated; German version EN 1092-1:2001— 71 стр.