Let X be a compact subset of the complex plane C. We denote by R0(X) the algebra consisting of the (restrictions to X of) rational functions with poles off X. Let m denote 2-dimensional Lebesgue measure. For/» > 1, let L"(X) = L"(X, dm). The closure of R0(X) in LP(X) will be denoted by Rr(X). Whenever p and q both appear, we assume that \/p + \/q = 1. If x is a point in X which admits a bounded...