Symmetric Functions in AC0A Can Be Computed in Constant Depth With Very Small Size. - Ingo Wegener; Norbert Wurm; Sang-Zin Yi (MFCS, 1990)

Optimal Depth, Very Small Size Circuits for Symmetric Functions in AC0. - Johan Håstad; Ingo Wegener; Norbert Wurm; Sang-Zin Yi (Inf. Comput., 1994)