Mackay, C. A., Phys. Rev.24 (1924) 319.
Kiess, C. C., and T. L. de Bruin, J. Res. Nat. Bur. Stand., Wash.4 (1930) 667.
Kuhn, H., Z. Phys.39 (1926) 77.
Senftleben, H., and E. Germer, Ann. Phys., Lpz.2 (1929) 847.
Rabinowitch, E., and W. C. Wood, J. chem. Phys.4 (1936) 358.
Massey, H. S. W., Negative ions; Cambridge, 1938.
Loeb, L. B., Fundamental processes of electrical discharge in gases; New York, 1939.
le Croisette, D. H., and J. Yarwood, J. sci. Instrum.28 (1951) 225.
Liehson, S. H., and H. Friedman, Rev. sci. Instrum.19 (1948) 303.
Verhagen, C. J. D. M., Thesis, Delft 1942.
Wilkinson, D. H., Ionization chambers and counters; Cambridge, 1950.
Hartog, H. den, Thesis, Amsterdams 1948.
Huber, P., F. Alder, E. Baldinger and F. Metzger, Helv. phys. Acta19 (1946) 207;20 (1947) 87.
Gemert, A. M. van, H. den Hartog and F. A. Muller, Physica9 (1942) 556.
Loosemore, W., and J. Sharpe, Nature167 (1951) 600.
Present, R. D., Phys. Rev.72 (1947) 243.
Montgomery, C. G., and Montgomery, D. D., Rev. sci. Instrum.18 (1947) 411. Appl. sci. Res. B. 3
