1. "Models and Modelers of Hydrogen";- Lakhtakia Akhlesh;American Journal of Physics,1996
2. - Sommerfeld, Arnold (1919). Atombau und Spektrallinien'. Braunschweig: Friedrich Vieweg und Sohn
3. - Richard Feynman, Quantum Electrodynamic, The book “The strange theory of light and matter” 1985
4. orcid.org/0000-0002-3965-121X (2019) Cardiac auscultation: normal and abnormal;- Warriner D;British Journal of Hospital Medicine
5. Improved Heart Sound Detection and Signal-to-Noise Estimation Using a Low-Mass Sensor;- Semmlow JL;IEEE Transactions on Biomedical Engineering,2016