REFERENCES
- Bose , J. C. 1928 . —The Motor Mechanism of Plants. London
- Clark , W. 1923 . —The Determination of Hydrogen Ions. Baltimore
- Creighton , H. J. 1928 . —Principles of Electrochemistry. London
- Cuthbert , J. B. 1930 . Trans. Roy. Soc. S. Afr. , xix pt. 1
- Czapek , F. 1905 . —Biochemie der Pflanzen. Jena
- Gordon and Lehmann . 1928 . Journ. Sci. Instr. , v
- Hall and Adams . 1929 . Journ. Am. Chem. Soc. , xli : 1515
- Jumelle , H. 1892 . Rev. Gen. de Bot., vol. , iv
- Noyes , W. A. 1921 . jun.— . Trans. Am. Electrochem. Soc. , xxxix : 451
- Rideal , E. K. 1926 . —An Introduction to Surface Chemistry. Cambridge
- Sievers . 1910 . B. Beil. 38 Jahresber. Ber. Landw. Marienberg, 1908; Bot. Centralb. , cxiii
- Smith , A. Lorrain. 1921 . —Lichens. Cambridge
- Tobler . 1909 . Ber. Deut. Bot. Ges. , xxvii