Gerhard Wullink Mark van Houdenhoven Erwin W. Hans Jeroen M. van Oostrum Marieke van der Lans Geert Kazemier Closing Emergency Operating Rooms Improves Efficiency. 543-546 2007 31 J. Medical Systems 6 http://dx.doi.org/10.1007/s10916-007-9096-6 db/journals/jms/jms31.html#WullinkHHOLK07