When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
By Ivar Ekeland. He is the founding editor of the "Annales de l Institut Henri Poincar -Analyse non lin aire" and he currently Editor in Chief of "Mathematics and Financial Economics". Author Ivar Ekeland.
When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.