C. C Apfel, O. S Cakmakkaya, G Frings, P Kranke, A Malhotra, A Stader, A Turan, A Biedler and K. Kolodzie
BJA: British Journal of Anaesthesia 103 ( 3 ): 359 - 363 , 2009
A Schnabel, S. U Reichl, P Kranke, E. M Pogatzki Zahn and P. K. Zahn
BJA: British Journal of Anaesthesia 105 ( 6 ): 842 - 852 , 2010