Lever-operated knapsack sprayers (IPPC document no. 53-A-84): by. H. H. Fisher and A. E. Deutsch, US Library of Congress No. 83-082988 (32 pp; US$5.00 inclusive of airmail or first class postage. Single copies free to Second, Third and Fourth World Countries and to non-commercial, non-profit organizations or institutions (or associated individuals) anywhere.). Oregon State University, Corvallis, Oregon 97331, USA: International Plant Protection Center. 1985