1. Electron Paramagnetic Resonance—Elementary Theory and Practical Applications;Weil,2007
2. Foundations of Modern EPR;Eaton,1998
3. Zavoisky and the discovery of EPR
4. http://en.wikipedia.org/wiki/File:EPR_methyl.png (22-01-19).
5. https://chem.libretexts.org (20-01-19).