Abstract:
By applying the main theorems on covering surface, a new normal criterion of algebroidal function was obtained. Let F be a family of k-valued algebroidal functions in a domain D of sphere V, and the branch points of F be isolated. If for all p∈D, there is a neighborhood U(p) such that for every ft∈F, there exist three different complex values at1,at2,at3 satisfying 3∑i=1¯n(U(p),ati,ft)≤1, then F is normal in D.