Presumed Self-portrait, circa 1512 Sanguine on paper, 13.1 in x 8.3 in // Royal Library of Turin, Italy

Study sheet with cats, dragon and other animals, between 1513 and 1515 Pen, ink, black chalk on paper, 10.66 in x 8.03 in // Royal Library at Windsor Castle, UK

Crossbow Machine, c.1481 Ink on paper Biblioteca Ambrosiana, Milan, Italy

Study for an equestrian monument, c.1485 - c.1490 Metalpoint on blue prepared paper, 5.98 in x 7.40 in // Royal Collection, UK

Saint Jerome in the Wilderness, between 1480 and 1482 Oil on panel, 40.5 in x 29.5 in // Pinacoteca Vaticana