Zhimin Zhang, Derivative Superconvergent Points in Finite Element Solutions of Harmonic Functions: A Theoretical Justification, Mathematics of Computation, Vol. 71, No. 240 (Oct., 2002), pp. 1421-1430 ...

Coefficient bounds for functions with a positive real part are used in a rather novel way to find sharp bounds for the first six coefficients of a function which is inverse to a regular normalized ...