1. ASTM E92-72.Vickers hardness of metallic materials.
2. ASTM E10-84.Brinell hardness of metallic materials.
3. ASTM E384-84.Microhardness of materials.
4. Comparison between the HRC, HRB and HV30 hardness scales maintained at the Istituto di Metrologia ‘G. Colonneti’ (IMGC), Turin, and those of the Orszàgos Mérésugyi Hivatal (OMH), Budapest;Barbato;Bulletin OIML No 82,1981
5. Comparison of hardness measurement between China (NIM) and Italy (IMGC);Barbato;Bulletin OIML No 105,1986