{{Cite journal| doi = 10.1186/s12873-022-00579-8| issn = 1471-227X (Electronic) 1471-227X (Linking)| volume = 22| issue = 1| pages = 23| last1 = Pietsch| first1 = U.| last2 = Mullner| first2 = R.| last3 = Theiler| first3 = L.| last4 = Wenzel| first4 = V.| last5 = Meuli| first5 = L.| last6 = Knapp| first6 = J.| last7 = Sollid| first7 = S. J. M.| last8 = Albrecht| first8 = R.| title = Airway management in a Helicopter Emergency Medical Service (HEMS): a retrospective observational study of 365 out-of-hospital intubations| journal = BMC Emerg Med| date = 2022-02-10| pmid = 35135493}}