<a href="https://en.wikipedia.org/wiki/Nicolaus_Copernicus" id="mwMA" rel="mw:WikiLink" title="Nicolaus Copernicus">Nicolaus Copernicus</a>'s book <i id="mwMQ"><a href="https://en.wikipedia.org/wiki/De_revolutionibus_orbium_coelestium" id="mwMg" rel="mw:WikiLink" title="De revolutionibus orbium coelestium">On the Revolutions of the Heavenly Spheres</a></i> is added to the <a href="https://en.wikipedia.org/wiki/Index_Librorum_Prohibitorum" id="mwMw" rel="mw:WikiLink" title="Index Librorum Prohibitorum">Index of Forbidden Books</a> 73 years after it was first published.