fractional integral, fractional derivatives, mapping properties, hypersingular integrals, Hölder spaces, Morrey spaces, Spaces of measurable functions (\(L^p\)-spaces, Orlicz spaces, Köthe function spaces, Lorentz spaces, rearrangement invariant spaces, ideal spaces, etc.), Lebesgue spaces, Fractional derivatives and integrals, variable exponent Lebesgue spaces, Riesz potential, grand spaces, variable exponent Hölder spaces