Perel, Pablo, Clayton, Tim, Altman, Doug G., Croft, Peter, Douglas, Ian, Hemingway, Harry, Hingorani, Aroon, Morley, Katherine I., Riley, Richard, Timmis, Adam, Van der Windt, Danielle, Roberts, Ian, "Red blood cell transfusion and mortality in trauma patients: risk-stratified analysis of an observational study", PLoS Medicine, 2014