1. C. Hermite, C.R. Acad. Sci. Paris 77, 226–233 (1873).
2. K. Mahler, Compos. Math. 19, 95–166 (1968).
3. J. Nuttall, J. Approx. Theory 42(4), 299–386 (1984).
4. J. Nuttall, in Pade and Rational Approximation (Academic, New York, 1977), pp. 101–109.
5. H. Stahl, Complex Variables Theory Appl., No. 4, 339–354 (1985).