On normal families
As main results of this paper, the author proves that a family of meromorphic functions \(f\) on the unit disc is normal if \(f\) satisfy either of the following conditions: (1) \(f(f')^m\) omits the value one, \(m\geq 2\); (2) \(f\neq 0\), \(f(f^{(k)})^m\) omits the value one, \(k,m\in \mathbb N\).
scientific article; zbMATH DE number 2135472