Classes of harmonic multivalent functions defined by subordination

This thesis consists of five chapters. In the first chapter, the aim and scope of the thesis are stated. In the second part, some basic definitions and theorems that will be used in the continuation of the thesis are given. In the third part, the material and method are mentioned. In the fourth chapter, the findings are mentioned. Some subclasses of multivalued harmonic functions defined by sabordination in the open unit disk and coefficient bounds and distortion theorems for functions belonging to these classes are given. In addition, extremal functions and convolution properties are obtained for these classes. In the fifth chapter, which is the last chapter, a general examination of the thesis is made.