IEC 60793-1-20:2001 Optical Fibres - Part 1-20: Measurement Methods and Test Procedures - Fibre Geometry (Edition 1.0; Together with the Other Standards in the IEC 60793-1-2X Series)
GOST R IEC 60793-1-21-2012 history
2012GOST R IEC 60793-1-21-2012 Optical fibres. Part 1-21. Measurement methods and test procedures. Coating geometry