{ "id": "1207.5551", "version": "v2", "published": "2012-07-23T22:30:54.000Z", "updated": "2012-11-15T19:57:40.000Z", "title": "One and two weight norm inequalities for Riesz potentials", "authors": [ "David Cruz-Uribe", "Kabe Moen" ], "comment": "v2 typos corrected. Illinois J. Math. to appear", "categories": [ "math.CA" ], "abstract": "We consider weighted norm inequalities for the Riesz potentials $I_\\alpha$, also referred to as fractional integral operators. First we prove mixed $A_p$-$A_\\infty$ type estimates in the spirit of [13, 15, 17]. Then we prove strong and weak type inequalities in the case $p