132 Mineral Nutrition of Plants 



31. Mattson, S., Ann. Agr. Coll. Sweden, 12:119 (1944). 



32. Mehlich, A., and Colwell, W. E., Soil Sei. Soc. Am. Proc, 8:179 

 (1944). 



33. Overstreet, R., Broyer, T. C, Isaacs, T. L., and Delwiche, C. C, 

 Am. f. Botany, 29:227 (1942). 



34. Overstreet, R., and Jacobson, L., Am. f. Botany, 33:107 (1946). 



35. Overstreet, R., and Jenny, H., Soil Sci. Soc. Am. Proc, 4:125 (1939). 



36. Overstreet, R., Ruben, S., and Broyer, T. C, Proc. Nat. Acad. Set. 

 U.S., 26:688 (1940). 



37. Parker, F. W., Soil Sci., 24:129 (1927). 



38. Peech, M., Diagnostic Techniques for Soils and Crops (Washington, 

 D. O, Am. Potash Inst., 1948). 



39. Ratner, E. I., Compt. rend. acad. sci. U.R.S.S., 42:313 (1944). 



40. , Compt. rend. acad. sci. U.R.S.S., 43:126 (1944). 



41. Schachtschabel, P., Erniihr. Pflanze, 35:132 (1939). 



42. Sengupta, K., Thesis, Univ. of Calif. Berkeley (1949). 



43. Sookne, A. M., and Harris, M., in Ott, E., ed., Cellulose and Cellulose 

 Derivatives (New York, Interscience Publ. Co., 1946) 113. 



44. Truog, E., Proc. First Intern. Congr. Soil Sci., 3:628 (1928). 



45. Vageler, P. W. E., Kationen- und Wasserhaushalt des Mineralbodens 

 (Berlin, J. Springer, 1932). 



46. Vlamis, J., Soil Sci., 67:453 (1949). 



47. Wanner, H., Vierteljahrsschr. naturjorsch. Ges. Zurich, 43:99 (1948). 



