British Standards Institution. (1970). Method for Rockwell superficial hardness test (N and T scales). British Standards Institution.
Dyfyniad Arddull ChicagoBritish Standards Institution. Method for Rockwell Superficial Hardness Test (N and T Scales). London: British Standards Institution, 1970.
Dyfyniad MLABritish Standards Institution. Method for Rockwell Superficial Hardness Test (N and T Scales). British Standards Institution, 1970.
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