1. OSHA. 1981, Occupational Safety and Health Administration - Department of Labor:Occupational Noise Exposure: Hearing Conservation Amendment. Federal Register, vol. 46, no 11, p. 4078. Washington, D.C., January 16.
2. OSHA. 1983, Occupational Safety and Health Administration - Department of Labor:Occupational Noise Exposure: Hearing Conservation Amendment; Final Rule. Federal Register. vol. 48. no. 46, p. 9738. Washington, D.C., March 8