PRIWITZER, T., URBAN, O., ŠPRTOVÁ, M., MAREK, M. V. Chloroplastic carbon dioxide concentration in Norway spruce(Picea abies L.Karst.)needles relates to the position withinthe crown. Photosynthetica. 1998, 35(4), 561-572. ISSN 0300-3604. E-ISSN 1573-9058.