1. The microwave gyrator;Hogan;Bell System Tech. J.,1952
2. IRE National Convention Record;Vartanian
3. Broad-band isolators and variable attenuators for millimeter wavelengths;Barnes;IRE Trans. Microwave Theory and Techniques,1961
4. Improved rectangular waveguide resonance isolators;Weiss;IRE Trans. Microwave Theory and Techniques,1956