Mitsuhiro Shimozawa Noriharu Suematsu Kenji Itoh Yoji Isota A Balanced Even Harmonic Quadrature Mixer Using Anti Parallel Diode Pairs. 1821-1828 2006 89-C IEICE Transactions 12 http://dx.doi.org/10.1093/ietele/e89-c.12.1821 db/journals/ieicet/ieicet89c.html#ShimozawaSII06