D Zhong, F Meng, W Yuan - Acta Mathematica Scientia, 2021 - Springer
Let f be a twice continuously differentiable self-mapping of a unit disk satisfying Poisson
differential inequality∣ Δ f (z)∣≤ B·∣ Df (z)∣ 2 for some B> 0 and f (0)= 0. In this note, we …