<a href="https://en.wikipedia.org/wiki/Max_Planck" id="mwbA" rel="mw:WikiLink" title="Max Planck">Max Planck</a> discovers <a href="https://en.wikipedia.org/wiki/Planck's_law" id="mwbQ" rel="mw:WikiLink" title="Planck's law">Planck's law</a> of black-body radiation.