Hilbert transforms along variable planar curves: Lipschitz regularity

In this paper, for $1<p<infty$, we obtain the $L^p$-boundedness of the Hilbert transform $H^{gamma}$ along a variable plane curve $(t,u(x_1, x_2)gamma(t))$, where $u$ is a Lipschitz function with small Lipschitz norm, and $gamma$ is a general curve satisfying some suitable smoothness and curvature conditions.