“…where f ∈ S ′ , ϕ ∈ S satisfying H ϕ dx = 0 and ϕ t (x) = t −γ ϕ(A −1 t x). Here S ′ denotes the space of tempered distributions and S the Schwartz space, which are the same as those in the Euclidean case (see [19]); also the convolution F * G for F, G ∈ L 1 is defined by We refer to [4] and [21,13,14] for the study of Littlewood-Paley operators and singular integrals, respectively, on L p spaces for homogeneous groups, 1 ≤ p < ∞.…”