<p>La recepta per fer un mapa d'edificis com el d'Amsterdam </p>
<p><a href="http://www.wired.com/wiredscience/2013/10/how-to-map-building-ages-in-your-home-town/">http://www.wired.com/wiredscience/2013/10/how-to-map-building-ages-in-your-home-town/</a></p>
<p>Raf</p>