1. Aarnio, B.: Die Tontypen in SW-Finland. [Swedish. Summary in German.] Statens Markforskn. Agrogeol. Medd. Helsingfors 28, 21 pp. (1928).
2. Alben, A. O., J. R.C.ole and R.D. Lewis: Chemical treatment of pecan rosette. Phytopathology 22, 595–601 (1932).
3. Albrecht, W. A.: Nutrition via soil fertility according to the climatic pattern. Contrib. Dept. Soils, Missouri Agricult. Exper. Stat., J., Ser. No 1153, 30 pp., 1949.
4. Anderson, A.J.: Molybdenum deficiency on a south Australian ironstone soil. J. Austral. Inst. Agricult. Sci. 8, 73–75 (1942).
5. Anderson, A.J., and D.V. Move: Lime and molybdenum in clover development on acid soils. Austral. J. Agricult. Res. 3, 95–110 (1952).