@Article{TAC-20_Ferrante-Lanzon-Brogliato,
 author       = "Ferrante, A. and Lanzon, A. and Brogliato, B.",
 title        = "A direct proof of the equivalence of side conditions for strictly positive real matrix transfer functions",
 journal      = "{IEEE} Transactions on Automatic Control",
 volume       = 65,
 number       = 1,
 pages        = "450-452",
 doi          = "10.1109/TAC.2019.2918123",
 month        = jan,
 year         = 2020}