## Normal families of meromorphic functions and shared values.(English)Zbl 1253.30047

In [Arch. Math. 59, No. 1, 50–54 (1992; Zbl 0758.30028)], W. Schwick first proved a normality criterion for a family of meromorphic functions which involves value sharing. This result inspired a number of researchers to establish normality criteria using the concept of value sharing. In the paper under review the authors prove two normality criteria for a family of meromorphic functions when $$P(f)f^{(k)}$$ and $$P(g)g^{(k)}$$ share a nonzero value for every pair of functions $$f$$, $$g$$ of the family, where $$P$$ is a polynomial having some special properties.

### MSC:

 30D45 Normal functions of one complex variable, normal families 30D35 Value distribution of meromorphic functions of one complex variable, Nevanlinna theory

### Keywords:

meromorphic function; normal family; shared value

Zbl 0758.30028
Full Text:

### References:

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