The standard defines the method of indicating on drawings, with the exception of engine drawings, the instructions for the marking of parts and assemblies for aerospace applications.
DIN EN 2851:1992 history
1992DIN EN 2851:1992-05 Aerospace series; marking of parts and assemblies other than engines; indications on drawings; german version EN 2851:1989
1992DIN EN 2851:1992 Aerospace series; marking of parts and assemblies other than engines; indications on drawings; german version EN 2851:1989