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3. Trace concentrations of anesthetic gases: a critical review of their disease potential;Ferstanding;Anesth Analg,1978
4. Is there a health hazard in anaesthetic practice?;Spence;Br J Anaesth,1978
5. Pollution of delivery ward air by nitrous oxide-methoxy-flurane;Dahlgren;Am Ind Hyg Assoc J,1979