Grossman-Clarke, S., Kimball, B., Hunsaker, D., Long, S. G., Kartschall, T., Wall, G., Printer Jr., P., Wechsung, F., LaMorte, R. (1999): Effects of elevated atmospheric CO2 on canopy transpiration in senescent spring wheat. - Agricultural and Forest Meteorology, 93, 2, 95-109.