Hans Schwerdtfeger 
Geometry of Complex Numbers 

The elements of abstract algebra have almost everywhere found a place in the undergraduate courses of universities, but this has happened to some extent at the expense of courses on geometry. Therefore a book which applies some notions of algebra to geometry, showing in a deliberately restricted domain their interrelation with geometrical ideas, is a useful counterbalance in the present trend to generalization and abstraction. This book should be of great value to students of mathematics in their second or third year at the university and be used by them concurrently with an introductory course on functions of a complex variable. It should give them a basis for the geometrical aspects of this theory and simultaneously help them to extend their understanding of the connections between some classical branches of geometry. It will also be useful to anyone, from pure mathematician to electrical engineer, who wishes to deepen his knowledge of the complex number system.