Displaying similar documents to “Strong converse inequality for a spherical operator.”

On the five-point theorems due to Lappan

Yan Xu (2011)

Annales Polonici Mathematici

Similarity:

By using an extension of the spherical derivative introduced by Lappan, we obtain some results on normal functions and normal families, which extend Lappan's five-point theorems and Marty's criterion, and improve some previous results due to Li and Xie, and the author. Also, another proof of Lappan's theorem is given.