@article {3596,
	title = {Acid Deposition Alters Red Spruce Physiology: Laboratory Studies Support Field Observations},
	journal = {Canadian Journal of Forest Research},
	volume = {23},
	year = {1993},
	month = {March},
	pages = {380-386},
	keywords = {Acid rain, Red spruce, Soil acidity},
	author = {McLaughlin, Samuel B and Tjoelker, Mark G and Roy, W. Kelly}
}
@article {4656,
	title = {Increased Dark Respiration and Calcium Deficiency of Red Spruce in Relation to Acidic Deposition at High-elevation Southern Appalachian Mountain Sites},
	journal = {Canadian Journal of Forest Research},
	volume = {21},
	year = {1991},
	pages = {1234-1244},
	keywords = {Red spruce, Soil acidity, Topography, Trees -- Growth},
	author = {McLaughlin, Samuel B and Andersen, Christian P and Hanson, Paul J and Tjoelker, Mark G and Roy, W. Kelly}
}
