Blazek, Vladimir, Boudewijn Venema, Steffen Leonhardt, and Paul Blazek. “Customized Optoelectronic In-Earsensor Approaches for Unobtrusive Continuous Monitoring of Cardiorespiratory Vital Signs”. International Journal of Industrial Engineering and Management 9, no. 4 (December 30, 2018): 197–203. Accessed November 22, 2024. https://ijiemjournal.uns.ac.rs/index.php/ijiem/article/view/143.