Toward the ergodicity of $p$-adic 1-Lipschitz functions represented by   the van der Put series
  Yurova \cite{Yu} and Anashin et al. \cite{AKY1, AKY2} characterize the ergodicity of a 1-Lipschitz function on $\Z_2$ in terms of the van der Put expansion. Motivated by their recent work, we provide the sufficient conditions for the ergodicity of such a function defined on a more general setting $\Z_p$.   In addition, we provide alternative proofs of two criteria (because of \cite{AKY1, AKY2} and \cite{Yu}) for an ergodic 1-Lipschitz function on $\Z_2,$ represented by both the Mahler basis and the van der Put basis. 
Sangtae Jeong
math.NT