Szmajda, Mirosław, Mirosław Chyliński, Jerzy Sacha, and Janusz Mroczka. “Three Methods for Determining Respiratory Waves from ECG (Part I)”. Metrology and Measurement Systems 30, no. 4 (December 30, 2023): 821–837. Accessed October 15, 2026. https://wydawnictwo.pan.pl/index.php/mms/article/view/5249.