1. Identification of hard contact lenses by their specific gravity.;Refojo;Int Contact Lens Clin,1984
2. Identifying rigid materials.;Hoffman;Contact Lens Forum,1985
3. Effectiveness of the Opti-mis system in differentiating PMMA from rigid gas permeable contact lenses.;Morton;CLAO J,1987
4. Qualitative identification of rigid gas permeable contact lens materials by densitometry.;Arce;CLAO J,1999
5. Identification of rigid gas permeable contact lens materials by means of ultraviolet-visible spectrophotometry.;Dain;Optom Vis Sci,1993