American Society for Metals, Westbrook, J. H., & Conrad, H. (1973). The science of hardness testing and its research applications: Based on papers presented at a symposium of the American Society for Metals, October 18 to 20, 1971. American Society for Metals.
শিকাগো স্টাইল (17 তম সংস্করণ) উদ্ধৃতিAmerican Society for Metals, J. H. Westbrook, এবং Hans Conrad. The Science of Hardness Testing and Its Research Applications: Based on Papers Presented at a Symposium of the American Society for Metals, October 18 to 20, 1971. Metals Park, Ohio: American Society for Metals, 1973.
M.L.A (8 ম সংস্করণ) উদ্ধৃতিAmerican Society for Metals, et al. The Science of Hardness Testing and Its Research Applications: Based on Papers Presented at a Symposium of the American Society for Metals, October 18 to 20, 1971. American Society for Metals, 1973.