设k为一个正整数,a(z)( 0,∞)为区域D的亚纯函数,F是区域D内的一族亚纯函数,其零点的重级至少为k.若对于任意f∈F,f(z)=0f^(k)(z)=a(z) 0〈|f^(k+1)(z)-a′(z)|〈|a(z)|,则F在D内正规.
Let k be a positive integer, a(z)( 0, ∞) be meromorphic functions on a domain D, F be a family of meromorphic functions on D, all of whose zeros have multiplicity at least k. If, for each f∈F,f(z)=0f^(k)(z)=a(z) 0〈|f^(k+1)(z)-a′(z)|〈|a(z)|, then F is normal on D.