Lewis, Gilbert N. (1916). "The Atom and the Molecule". Journal of the American Chemical Society. 38 (4): 762–785. doi:10.1021/ja02261a002. Retrieved 21 March 2024. http://scarc.library.oregonstate.edu/coll/pauling/bond/papers/corr216.3-lewispub-19160400-02.html ↩
Jean Maruani (1989). Molecules in Physics, Chemistry and Biology: v. 3: Electronic Structure and Chemical Reactivity. Springer. p. 73. ISBN 978-90-277-2598-1. Retrieved 14 March 2013. 978-90-277-2598-1 ↩