Approximation and the topology of rationally convex sets
  Considering a mapping g holomorphic on a neighbourhood of a rationally convex set K in $C^n$, and range into the complex projective space $P^m$, the main objective of this paper is to show that we can uniformly approximate g on K by rational mappings defined from $C^n$ into $P^m$. We only need to ask that the second Cech cohomology group $\check{H}^2(K)$ vanishes. 
Eduardo S. Zeron