DIN EN ISO 8598-1:2015-01 Optics and optical instruments - Focimeters - Part 1: General purpose instruments (ISO 8598-1:2014); German version EN ISO 8598-1:2014
2015DIN EN ISO 8598-1:2015-01 Optics and optical instruments - Focimeters - Part 1: General purpose instruments (ISO 8598-1:2014); German version EN ISO 8598-1:2014