Atomic transitions in the Bohr model of the sodium atom
<a href="https://de.wikipedia.org/wiki/User:Orci" class="extiw" title="de:User:Orci">Orci</a>
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correction of [Image:Energy levels of hydrogen atom.png] by <a href="https://hu.wikipedia.org/wiki/User:SzD%C3%B3ri" class="extiw" title="hu:User:SzDóri">Dorottya Szam</a>