Suleyman S. Kozat Michail Vlachos Claudio Lucchese Helga Van Herle Philip S. Yu Embedding and Retrieving Private Metadata in Electrocardiograms. 241-259 2009 33 J. Medical Systems 4 http://dx.doi.org/10.1007/s10916-008-9185-1 db/journals/jms/jms33.html#KozatVLHY09