BS ISO 424:1994
Photography. Processing chemicals. Specification for anhydrous sodium carbonate and sodium carbonate monohydrate
ISO 424:1994
Photography — Processing chemicals — Specifications for anhydrous sodium carbonate and sodium carbonate monohydrate
ISO 3942:1976
Photographic grade sodium carbonate, monohydrate — Specification
KS M ISO 746-2019
Sodium carbonate for industrial use — Determination of matter insoluble in water at 50 degrees C