Williams , S. (1942). Hardness and hardness measurements. Cleveland, OH.: American Society for Metals.
Παραπομπή Chicago StyleWilliams , Samuel. Hardness and Hardness Measurements. Cleveland, OH.: American Society for Metals, 1942.
Παραπομπή MLAWilliams , Samuel. Hardness and Hardness Measurements. Cleveland, OH.: American Society for Metals, 1942.
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