Ion leaching in forest ecosystems along a Great Lakes air pollution gradient. Journal of Environmental Quality. 21(4):614-623.. 1992.
Foliar sulfur and nitrogen along an 800-km pollution gradient. Canadian Journal of Forest Research. 22:1761-1769.. 1992.
Environmental stress effects on vigor, mortality, and growth in northern hardwood forests along a pollution-climate gradient. The Michigan Academician. 30:27-47.. 1998.
Cation and anion fluxes in northern hardwood throughfall along an acidic deposition gradient. Canadian Journal of Forest Research. 23:457-467.. 1993.
Soil solution chemistry and ion leaching in northern hardwood forests across an 800 km pollution gradient. Emerging Issues in Northern Hardwood Management: Air Pollution, Climate Change & Biodiversity. Miscellaneous Publication 91-1:38.. 1991.
Comparison of cation leaching in five northern hardwood stands along an air pollution gradient using a throughfall modelling approach. IUFRO World Congress Proceedings. :295-306.. 1990.
Studying the effects of air pollution on forest along exposure gradients: experiences in the United States and opportunities for cooperation. Climate and Atmospheric Deposition Studies in Forests. :109-115.. 1994.