NF B52-001/A1:2009 Regulations governing the use of timber in structure - Visual classification for the use of French coniferous and deciduous sawn timber in structures.
2011NF B52-001-1:2011 Regulations governing the use of timber in structure - Visual classification for the use of French softwood and hardwood species in structures - Part 1 : massive wood.
2009NF B52-001/A1:2009 Regulations governing the use of timber in structure - Visual classification for the use of French coniferous and deciduous sawn timber in structures.