1. Nitrification in forest soil after refertilization with urea or urea and dicyandiamide;Aarnio;Soil Biol. Biochem.,1992
2. Alexandersson, H., Karlström, C., Larsson-McCann, S., 1991. Temperature and precipitation in Sweden 1961–1990, reference normals. Swedish Meteorological and Hydrological Institute, Meteorologi nr 81. Norrköping, 88 p. (in Swedish).
3. Andersson, F., Bergholm, J., Hallbäcken, L., Möller, G., Pettersson, F., Popovic, B. 1995. The Farabol field experiment — Acidification, liming and nitrogen fertilization of a Norway spruce forest in south-east Sweden. Swedish University of Agricultural Sciences, Department of Ecology and Environmental Sciences. Report No. 70. Uppsala., 136 p. (in Swedish, with English abstract and summary).
4. Anon., 1987. SAS/STAT, User’s guide for personal computers. Version 6, fourth edn. SAS Institute Inc., Cary, NC, 1686 p.
5. Anon., 1991. Skogsstyrelsens allmänna råd till ledning för användning av kvävegödselmedel på skogsmark. Forestry Board of Sweden, SKSFS 1991:2. Jönköping, 4 p. (in Swedish).