[3][neaktivna poveznica] "MDF Material Properties Data: Medium Density Fiberboard (MDF)"
royalsocietypublishing.org
rspb.royalsocietypublishing.org
journal=Proc. R. Soc. Lond. B, 1988. A. P. Jackson,J. F. V. Vincent and R. M. Turner: "The Mechanical Design of Nacre" [4][neaktivna poveznica]
springerlink.com
journal=Journal of Materials Science, 1981., "Spherical indentation of tooth enamel" M. Staines, W. H. Robinson and J. A. A. Hood [5][neaktivna poveznica]