Polygraph and audio synchronization applied to apnea event analysis based on non-negative matrix factorization. - Francisco David González Martínez; Juan De La Torre Cruz; Julio J. Carabias-Orti; Francisco J. Cañadas-Quesada; Alejandro Antonio Salvador-Navarro; José Ranilla; Lyam Lamrini-H. Laarbi (EURASIP J. Audio Speech Music. Process., 2025)