1. Y.Ralchenko A. E.Kramida J.Readerand NIST ASD Team (2008).NIST Atomic Datqbase (version 3.1.5) [Online]. Available athttp://physics.nist.gov/asd3[2008 October 10]. National Institute of Standards and Technology Gaithersburg MD USA.
2. The Spectrum of Atomic Hydrogen
3. The Amateur Scientist
4. An optical lattice clock with accuracy and stability at the 10−18 level