Effects of nitrogen deposition and empirical nitrogen critical loads for ecoregions of the United States
L.H. Pardo
M.E. Fenn
C.L. Goodale
L.H. Geiser
C.T. Driscoll
E.B. Allen
J.S. Barron
R. Bobbink
W.D. Bowman
C.M. Clark
B. Emmett
F.S. Gilliam
T.L. Greaver
S.J. Hall
E.A. Lilleskov
L. Liu
J.A. Lynch
K.J. Nadelhoffer
S.S. Perakis
M.J. Robin-Abbott
J.L. Stoddard
K.C. Weathers
R.L. Dennis
Ecological Applications (2011) 21: 3049–3082.