PDF a Article Papanicolaou, E.P. | Nobeli, C. | Loupassaki, M. | Skarlou, V. Fertilizer efficiency studies in citrus trees using isotopically labelled nitrogen fertilizers 1988 - Firenze University Press Is part of Advances in horticultural science [rivista dell'ortofloroftutticoltura italiana]. 2 (N.1), 1988