Jauhiainen J, Wallen B, Malmer N. Potential NH4+ & NO3- uptake in seven Sphagnum species. New Phytol. 1998  ;138:287-293.

Aerts R, Wallen B, Malmer N. Growth limiting nutrients in Sphagnum dominated bogs subject to low and high atmospheric Nitrogen supply. Journal of Ecology . 1992  ;80:131-40.