1. ACGIH (1976): “Documentation of the Threshold Limit Values.” 3rd Ed. Cincinnati, Ohio: American Conference of Governmental Industrial Hygienists.
2. ACGIH (1986): “Documentation of the Threshold Limit Values.” 5th Ed. Cincinnati, Ohio: American Conference of Governmental Industrial Hygienists.
3. Threshold Limit Values: A More Balanced Appraisal
4. ACGIH (1948): “Report of the committee on threshold limits.” Transactions of the 10th annual meeting of the American Conference of Governmental Industrial Hygienists, pp 29–31.
5. ACGIH (1953): “Report of the committee on threshold limits.” Transactions of the 15th Annual Meeting of the American Conference of Governmental Industrial Hygienists, pp 29–31.