@article{article0cde8071,
title   = {Human activities changing the nitrogen cycle in Brazil},
author = {Filoso, S and Martinelli, Luiz Antonio and Howarth, R W and Boyer, E W and Dentener, F},
year = {2006},
doi = {10.1007/s10533-006-9003-0},
journal   = {Biogeochemistry}
}