[44] Bull. de l’Acad. des Sciences Belg. (3) 9, pp. 327, 381, 1885; 12 p. 30, 1886.
[45] Communications from the Physical Laboratory, Leiden, No. 33, 1896; Phil. Mag. 43, p. 226; 44, pp. 55 and 255; and 45, p. 197.
[46] Arch. Néerl. 25, p. 190.
[47] Phil. Mag. 45, p. 325; 47, p. 165.
[48] Comptes rendus, 126, p. 181.
[49] Phil. Mag. 46, p. 187.
[50] Phil. Mag. 45, p. 348.
[51] Comptes rendus, 125, p. 865.
[52] Comptes rendus, pp. 748 and 949, 1897.
[53] Comptes rendus, 127, p. 216; 128, p. 45.