Berdén, M. (1994). Ion leaching and soil acidification in a forest Haplic Podzol: Effects of nitrogen application and clear-cutting. Swedish University of Agricultural Sciences, Dept. of Ecology and Environmental Research.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Berdén, Maria. Ion Leaching and Soil Acidification in a Forest Haplic Podzol: Effects of Nitrogen Application and Clear-cutting. Uppsala: Swedish University of Agricultural Sciences, Dept. of Ecology and Environmental Research, 1994.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Berdén, Maria. Ion Leaching and Soil Acidification in a Forest Haplic Podzol: Effects of Nitrogen Application and Clear-cutting. Swedish University of Agricultural Sciences, Dept. of Ecology and Environmental Research, 1994.
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