[11]. Le Bon, C. R. 130, p. 891, 1900.

[12]. Lenard, Annal. d. Phys. 1, p. 498; 3, p. 298, 1900.

[13]. Schmidt, Annal. d. Phys. 65, p. 141, 1898.

[14]. Mme Curie, C. R. 126, p. 1101, 1898.

[15]. Owens, Phil. Mag. Oct. 1899.

[16]. Rutherford, Phil. Mag. Jan. 1900.

[17]. M. and Mme Curie and G. Bemont, C. R. 127, p. 1215, 1898.

[18]. Giesel, Phys. Zeit. 3, No. 24, p. 578, 1902.

[19]. Giesel, Annal. d. Phys. 69, p. 91, 1890. Ber. d. D. Chem. Ges. p. 3608, 1902.

[20]. Demarçay, C. R. 127, p. 1218, 1898; 129, p. 716, 1899; 131, p. 258, 1900.