Essential norms of Volterra-type operators between~ZygmundZygmund~ type spaces

~In this paper, we investigate the boundedness of some Volterra-type operators between ~$Zygmund$~ type spaces. Then, we give the essential norms of such operators in terms of ~$g,\varphi$, their derivatives and the n-th power ~$\varphi^n$ of ~$\varphi$