American researchers discover the <a href="https://en.wikipedia.org/wiki/Codex_Madrid_(Leonardo)" id="mw7Q" rel="mw:WikiLink" title="Codex Madrid (Leonardo)">Madrid Codices</a> by <a href="https://en.wikipedia.org/wiki/Leonardo_da_Vinci" id="mw7g" rel="mw:WikiLink" title="Leonardo da Vinci">Leonardo da Vinci</a> in the <a href="https://en.wikipedia.org/wiki/Biblioteca_Nacional_de_España" id="mw7w" rel="mw:WikiLink" title="Biblioteca Nacional de España">National Library of Spain</a>.