Ársrit Ræktunarfélags Norðurlands - 01.01.1968, Page 17

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Heimildir.
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2. Larsen, Sigurd: The Use of !’■'’>2 in Studies on the Uptake of Phos-
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3. Lewis, D. G.; Quirk, J. P.: Diffusion of Phosphate in Soil. — Trans.
Int. Soc. Soil Sci. Joint Meet. Comm. IV & V, New Zeal. 1962. 132—
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4. Lundegárdh, Henrik: The Triple-Analysis Method of Testing Soil
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5. Olsen, Sterling R.; Cole, C. V.; Watanabe, Frank S.; Dean, L. A.:
Estimation of Available Phosphorus in Soils by Extraction With So-
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8. Steenbjerg, F.: Nogle virkninger af plantenæringsstoffer og pesti-
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