Vester AE, Christensen EF, Andersen SK, Tønnesen E. Ethical and practical problems in blood sampling for research purposes during pre-hospital emergencies. Acta Anaesthesiol Scand. 2005 Nov;49(10):1540–3. doi: 10.1111/j.1399-6576.2005.00789.x. PMID: 16223403.