“…By using the representation (1.1), many properties of harmonic mappings can be generalized to the polyharmonic mappings. This line of research was started in by S. Chen, Ponnusamy, Qiao, and Wang in [4,21], and continued by the third author with J. Chen and Wang in the series of articles [5,6,7,8,9] where, for example, the radii of univalency, starlikeness and convexity were studied for polyharmonic mappings.…”