During the last three decades, interest in the field of interaction of microwaves with ferrimagnetics has steadily increased. Investigations in tlris field have led to the development of a number of devices used for a variety of applications. The initial emphasis of the investigators was on the microwave behavior of ferrimagnetics placed in cavities and metallic waveguides and associated devices. This work has been presented in various books, monographs, and reviews written during the sixties. In recent years, interest in microwave propagation in ferrimagnetics has shifted from loaded...