1. Field measurements on the dissociation of ammonium nitrate and ammonium chloride aerosols;Allen;Atmospheric Environment,1989
2. Sampling of nitrates in ambient air;Appel;Atmospheric Environment,1981
3. Evaluation of procedures for measuring atmospheric nitric acid and ammonia;Appel;Atmospheric Environment,1988
4. Studies of dry acid deposition in the south coast air basin: intermethod comparison of procedures for nitric acid and ammonia;Appel;Final Report to the California Air Resources Board, Contract No. 4-147-32,1986
5. Determination of acidity in ambient air;Appel;Final Report to the California Air Resources Board, Contract No. A1-159-32,1984