[1]  Muckenhoupt B, Wheeden  R L. Weighted norm inequalities for fractional integrals. Trans Amer Math Soc, 1974, 192:  261--274

[2] Bernardis A, Hartzstein S, Pradolini G. Weighted inequalities for commutators of  fractional integrals on spaces of homogeneous type. J Math Anal Appl, 2006, 322: 825--846

[3] Riveros M S. Weighted inequalities for generalized fractional operators. Rev Un Mat Argentina, 2008, 49(2): 29--38

[4] O'Neil R. Fractional integration in Orlicz spaces. Trans Amer Math Soc, 1963, 115: 300--328

[5] Lorente M, Martell J M, Riveros M S, Torre A. Generalized H\"{o}rmander's conditions, commutators and weights. J Math Anal Appl, 2008, 342(2): 1399--1425

[6] Chanillo S, Watson D K, Wheeden R L. Some integral and maximal operators related to starlike sets. Studia  Math, 1993, 107(3): 223--255

[7] Garcia-Cuerva J, Rubio de Francia J L. Weighted Norm Inequalities and Related Topics. Amsterdam: North-Holland, 1985

[8] Cruz-Uribe D, Martell J M, Përez C. Extrapolation from A_∞ weights and applications. J Funct Anal, 2004, 213: 412--439

[9] Fefferman C, Stein E M. H^p spaces in several variables. Acta Math, 1972, 129: 137--193

[10]  Pèrez C, Trujillo-Gonzalez R. Sharp weighted estimates for multilinear commutators. J London Math Soc, 2002, 65(2): 672--692