3 standards here:

ISO 9407:1991 Shoe sizes -- Mondopoint system of sizing and marking
ISO/TS 19407:2015 Footwear -- Sizing -- Conversion of sizing systems
ISO/TS 19408:2015 Footwear -- Sizing -- Vocabulary and terminology


1 is missing:

ISO 9407:1991 Shoe sizes -- Mondopoint system of sizing and marking


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