The uniform convergence of a double sequence of functions at a point and Korovkin-type approximation theorems (Q2048242)

In this paper, the authors considered a new kind of uniform convergence of a double sequence of functions at a point. They have given an example and demonstrated a Korovkin-type approximation theorem for a double sequence of functions using the uniform convergence at a point. Then they have shown that their result is stronger than the Korovkin theorem given by Volkov. In the last section, they studied the rates of convergence via a new kind of convergence.