1. NIOSH dermatology program;U.S. Department of Health, Education and Welfare,1980
2. Occupational skin disease;Samitz,1983
3. Risk factors in occupational skin disease;Cohen,1982
4. Occupational marks and other physical signs;Oppenheim,1948
5. Occupational koilonychia of the toe nails;Bentley-Phillips;Br J Dermatol,1971