Gas exchange, leaf nitrogen, and growth efficiency of Populus tremuloides in a CO2-enriched atmosphere. Ecological Applications. 10(1):3-17.. 2000.
Gender-specific responses of Populus tremuloides to atmospheric CO2 enrichment. New Phytologist. 150:675-684.. 2001.
Genotypic variation in physiological and growth responses of Populus tremuloides to elevated atmospheric CO2 concentration. Tree Physiology. 20:1019-1028.. 2000.
A meta-analysis of elevated CO2 effects on woody plant mass, form, and physiology. Oecologia. 113:299-313.. 1998.
Sex-specific physiological and growth responses to elevated atmospheric CO2 in Silene latifolia Poiret. Global Change Biology. 9(4):612-618.. 2003.