1. ES Bernhardt, MA Palmer, and JD Allan .2005 .Synthesizing US river restoration efforts .Science,308:636 -37 .
2. FH Bormann, and GE Likens .1967 .Nutrient cycling .Science,155:424 -29 .
3. NL Bradley, AC Leopold, J. Ross, and W. Huffaker .1999 .Phenological changes reflect climate change in Wisconsin .P Natl Acad Sci USA,96:9701 -04 .
4. TJ Butler, GE Likens, and BJB Stunder .2001 .Regional-scale impacts of Phase I of the Clean Air Act Amendments in the USA: the relation between emissions and concentrations, both wet and dry .Atmos Environ,35:1015 -28 .
5. TJ Butler, GE Likens, FM Vermeylen, and BJB Stunder .2005 .The impact of changing nitrogen oxide emissions on wet and dry nitrogen deposition in the northeastern USA .Atmos Environ,39:4851 -62 .