M. Staines, W. H. Robinson & J. A. A. Hood. (1981). «Spherical indentation of tooth enamel» Journal of Materials Science 16 (9): 2551–2556. doi:10.1007/bf01113595. Bibcode: 1981JMatS..16.2551S..
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M. Staines, W. H. Robinson & J. A. A. Hood. (1981). «Spherical indentation of tooth enamel» Journal of Materials Science 16 (9): 2551–2556. doi:10.1007/bf01113595. Bibcode: 1981JMatS..16.2551S..