Bosac, C., Gardner, S.D.L., Taylor, G. and Wilkins, D. 1995. Elevated CO2 and hybrid poplar: a detailed investigation of root and shoot growth and physiology of Populus euramericana, 'Primo'. 1995. Forest Ecology and Management 74: 103-116.

Calfapietra, C., Gielen, B., Sabatti, M., De Angelis, P., Miglietta, F., Scarascia-Mugnozza, G. and Ceulemans, R. 2003b. Do above-ground growth dynamics of poplar change with time under CO2 enrichment? New Phytologist 160: 305-318.

Curtis, P.S., Vogel, C.S., Pregitzer, K.S., Zak, D.R., and Teeri, J.A. 1995. Interacting effects of soil fertility and atmospheric CO2 on leaf area growth and carbon gain physiology in Populus x euramericana (Dode) Guinier. New Phytologist 129: 253-263.

Gielen, B., Calfapietra, C., Lukac, M., Wittig, V.E., de Angelis, P., Janssens, I.A., Moscatelli, M.C., Grego, S., Cotrufo, M.F., Godbold, D.L., Hoosbeek, M.R., Long, S.P., Miglietta, F., Polle, A., Bernacchi, C.J., Davey, P.A., Ceulemans, R. and Scarascia-Mugnozza, G.E. 2005. Net carbon storage in a poplar plantation (POPFACE) after three years of free-air CO2 enrichment. Tree Physiology 25: 1399-1408.

Guo, B., Dai, S., Wang, R., Guo, J., Ding, Y. and Xu, Y. 2015. Combined effects of elevated CO2 and Cd-contaminated soil on the growth, gas exchange, antioxidant defense, and Cd accumulation of poplars and willows. Environmental and Experimental Botany 115: 1-10.

Lagomarsino, A., De Angelis, P., Moscatelli, M.C. and Grego, S. 2009. The influence of temperature and labile C substrates on heterotrophic respiration in response to elevated CO2 and nitrogen fertilization. Plant and Soil 317: 223-234.

Liberloo, M., Calfapietra, C., Lukac, M., Godbold, D., Luo, Z.-B., Polle, A., Hoosbeek, M.R., Kull, O., Marek, M., Raines, C., Rubino, M., Taylor, G., Scarascia-Mugnozza, G. and Ceulemans, R. 2006. Woody biomass production during the second rotation of a bio-energy Populus plantation increases in a future high CO2 world. Global Change Biology 12: 1094-1106.

Liberloo, M., Dillen, S.Y., Calfapietra, C., Marinari, S., Luo, Z.B., De Angelis, P. and Ceulemans, R. 2005. Elevated CO2 concentration, fertilization and their interaction: growth stimulation in a short-rotation poplar coppice (EUROFACE). Tree Physiology 25: 179-189.

Liberloo, M., Gielen, B., Calfapietra, C., Veys, C., Pigliacelli, R., Scarascia-Mugnozza, G. and Ceulemans, R. 2004. Growth of a poplar short rotation coppice under elevated atmospheric CO2 concentrations (EUROFACE) depends on fertilization and species. Annals of Forest Science 61: 299-307.

Wang, R., Dai, S., Tang, S., Tian, S., Song, Z., Deng, X., Ding, Y., Zou, X., Zhao, Y. and Smith, D.L. 2012. Growth, gas exchange, root morphology and cadmium uptake responses of poplars and willows grown on cadmium-contaminated soil to elevated CO2. Environmental Earth Sciences 67: 1-13.