[14] Wied. Ann. 44, p. 377.

[15] Wied. Ann. 43, p. 280.

[16] Zeitschrift f. physikal. Chem. 11, p. 753.

[17] Phil. Mag. [5] 3, p. 321.

[18] Ann. de chim. et de phys. [6] 4, p. 433; 9, p. 65; 10, p. 200.

[19] Wied. Ann. 23, p. 228; 27, p. 191.

[20] Wied. Ann. 39, p. 25.

[21] Wied. Ann. 42, p. 115.

[22] Phil. Mag. [5] 12, p. 171.

[23] Journ. de Phys. 1884, p. 360.