http://www.geocaching.com/geocache/GC2E1EW_mulhousien-celebre-francois-spoerry?guid=1a6798b7-b15d-440f-85b4-a8ab007b4d6b

http://www.lalsace.fr/haut-rhin/2012/05/23/l-oeuvre-de-francois-spoerry

http://en.wikipedia.org/wiki/Fran%C3%A7ois_Spoerry