1998ISO 8257-1:1998 Plastics - Poly(methyl methacrylate) (PMMA) moulding and extrusion materials - Part 1: Designation system and basis for specifications
1987ISO 8257-1:1987 Plastics; Poly(methyl metacrylate) (PMMA) moulding and extrusion materials; Part 1 : Designation