@article{articlef2013eb4,
title   = {Does nitrogen uptake affect nitrogen uptake efficiency, or vice versa?},
author = {Samborski, Stanislaw and Kozak, Marcin and Azevedo, Ricardo Antunes de},
year = {2008},
doi = {10.1007/s11738-008-0164-4},
journal   = {Acta Physiologiae Plantarum}
}