Boris R. Andrievsky Alexander L. Fradkov Information Transmission by Means of Chaos-Based Frequency Modulation and Adaptive Identification. 42-46 2007 CCA https://doi.org/10.1109/CCA.2007.4389203 conf/IEEEcca/2007 db/conf/IEEEcca/IEEEcca2007.html#AndrievskyF07