ISO 3601-1/Cor1:2009 - Fluid power systems - O-rings - Part 1: Inside diameters, cross-sections, tolerances and size identification code - Corrigendum 1
ISO 3601 A o-ring size listing - Maryland Metrics
4. Size List - O-Rings-Stock O-Ring Webshop
History of the ISO 3601 Series of Standards for O-Rings - Fluid Power Journal
4. Size List - O-Rings-Stock O-Ring Webshop
O-Ring Size Charts: AS568 & Metric | Global O-Ring and Seal