@article {ARC22397, title = {Mycorrhizal fungi supply nitrogen to host plants in arctic tundra and boreal forests: 15N is the key signal}, journal = {Canadian Journal of Microbiology}, volume = {55}, year = {2009}, pages = {84-94}, doi = {10.1139/W08-127}, author = {John E. Hobbie and Erik A. Hobbie and J. C. Weber and J. Shamhart and H. Drossman and M. H. Conte} }