1. Aitken J 1881: Trans. Roy. Soc. Edinbg., 30, 337–368.
2. Barkow E 1906: Marburg, Diss. Ann. d. Phys., 4, 23, 317–344.
3. Battelli A 1891: Nuovo Cimento, 3, 29, 97–131.
4. Clausius R 1849: Ann. d. Phys. u. Chem., 76, 161–188.
5. Coulier P J 1875: Journ. de Pharmacie et de Chimie, 4, 22, 165–173.