L.C. Pearson and Donald B. Lawrence's "Photosynthesis in Aspen Bark During Winter Months." Reprinted from the American Journal of Botany article called "Photosynthesis in Aspen Bark" by L.C. Pearson and D.B. Lawrence.
Copy of "Influence of Temperature and Humidity on Distribution of Lichens in a Minnesota Bog" by L.C. Pearson, reprinted from Ecology, Vol. 50, No. 4, Summer, 1969
