Bivariate quartic spline spaces and quasi-interpolation operators

In this paper, we study two bivariate quartic spline spaces S"4^3^,^2(@D"m"n^(^2^)) and S"4^2^,^3(@D"m"n^(^2^)), and present two classes of quasi-interpolation operators in the two spaces, respectively. Some results on the operators are given.