Qs. Lai, WEIGHTED INTEGRAL-INEQUALITIES FOR THE HARDY TYPE OPERATOR AND THE FRACTIONAL MAXIMAL OPERATOR, Journal of the London Mathematical Society, 49, 1994, pp. 244-266
Let w(x), u(x) and v(x) be weight functions. In this paper, under appr
opriate conditions on Young's functions PHI1, PHI2 we characterize the
inequality PHI2(-1)(integral-infinity/0 PHI2(Tf(x))w(x)dx) less-than-
or-equal-to PHI1(-1)(integral-infinity/0 PHI1(Cf(x)u(x))v(x)dx) for th
e Hardy-type operator T defined in [1] and the inequality PHI2-1(integ
ral(Rn) PHI2(M(alpha,nu)(fv)(x))w(x)dv(x)) less-than-or-equal-to PHI1(
-1) (integral(Rn) PHI1(Cf(x))v(x)dv(x)) for the fractional maximal ope
rator M(alpha,v) defined in [8], as well as the corresponding weak-typ
e inequalities.