{{Cite journal| doi = 10.1016/j.bjoms.2014.03.018| issn = 1532-1940 (Electronic) 0266-4356 (Linking)| volume = 52| issue = 6| pages = 518–22| last1 = Buttner| first1 = M.| last2 = Schlittler| first2 = F. L.| last3 = Michel| first3 = C.| last4 = Exadaktylos| first4 = A. K.| last5 = Iizuka| first5 = T.| title = Is a black eye a useful sign of facial fractures in patients with minor head injuries? A retrospective analysis in a level I trauma centre over 10 years| journal = Br J Oral Maxillofac Surg| date = 2014-05-06| pmid = 24793410}}