Saleh A. J., Zhang L., Hadi S. M. and Ouyang W. (2014) “A priming dose of intravenous ketamine-dexmedetomidine suppresses fentanyl-induced coughing: A double-blind, randomized, controlled study”, Upsala Journal of Medical Sciences, 119(4), pp. 333–337. doi: 10.3109/03009734.2014.968270.