1. References and details regarding the history sketched in this paragraph can be found in Rocke, A. J. Chemical Atomism in the Nineteenth Century; Ohio State University Press: Columbus, 1984.
2. (1881), as reported on pp. 278 to 284 in Volume II of Leo Koenigsberger, Hermann von Helmholtz (Verlag Vieweg, Braunschweig, 1902).
3. THE ATOM AND THE MOLECULE.
4. Wechselwirkung neutraler Atome und hom�opolare Bindung nach der Quantenmechanik