Barzanji, A., Zareiyan, A., Nezamzadeh, M. and Mazhari, M.S. 2019. Evaluation of Observational and Behavioural Pain Assessment Tools in Nonverbal Intubated Critically Adult Patients after Open - Heart Surgery: A Systematic Review. Open Access Macedonian Journal of Medical Sciences. 7, 3 (Jan. 2019), 446–457. DOI:https://doi.org/10.3889/oamjms.2019.103.