“…Since variable exponent function spaces have widely used in many fields such as electrorheological fluid [ 43 ], differential equations [ 19 , 23 , 41 ] and image restoration [ 9 , 22 , 29 , 34 , 46 ], many classical constant exponent function spaces have been generalized to variable exponent setting, such as variable exponent Bessel potential spaces [ 4 , 21 ], variable Hajłasz–Sobolev spaces [ 5 ], variable exponent Besov and Triebel–Lizorkin spaces [ 3 , 13 , 16 , 27 , 30 , 31 , 49 ], variable exponent Hardy spaces [ 38 , 56 ], variable exponent Morrey spaces [ 2 ], variable exponent Herz spaces [ 1 , 26 , 44 ], variable exponent Herz-type Hardy spaces [ 18 , 28 , 48 ], variable exponent Herz–Morrey Hardy spaces [ 50 ], variable exponent Herz-type Besov and Triebel–Lizorkin spaces [ 14 , 17 , 45 , 52 ], variable exponent Morrey-type Besov and Triebel–Lizorkin spaces [ 20 ], Herz–Morrey-type Besov and Triebel–Lizorkin spaces with variable exponents [ 15 ], Triebel–Lizorkin-type spaces with variable exponents [ 57 ], variable weak Hardy spaces [ 53 ], Besov-type spaces with variable smoothness and integrability [ 58 ], variable integral and smooth exponent Triebel–Lizorkin spaces associated with a non-negative self-adjoint operator [ 51 ], variable exponent Hardy spaces associated with operators [ 55 ], and variable Hardy spaces associated with operators [ 54 , 59 , 60 ]. For the boundedness of integral operators in variable function spaces, we recommend [ 32 ] and [ 33 ].…”