Shahiri TS, Richebe P, Richard-Lalonde M, Gelinas C, et al. Description of the validity of the Analgesia Nociception Index (ANI) and
Nociception Level Index (NOL) for nociception assessment in anesthetized patients
undergoing surgery: a systematized review. J Clin Monit Comput 2021 Nov 16. pii: 10.1007/s10877-021-00772.
PMID: 34783941