The atomic number corresponds to the number of protons in the nucleus of an atom of that element. It also corresponds to the number of electrons in the neutral atom.
- International Union of Pure & Applied Chemistry: Commission on the Nomeclature of Inorganic Chemistry, Nomenclature of Inorganic Chemistry Recommendations 2005, Eds. N.G. Connelly, T. Damhus, R.M. Hartshorn, and A.T. Hutton, Royal Sociery of Chemistry, 2005. ISBN-13: 978-0854044382.