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Langdon J, Williams DM, Navsaria H, Leigh IM.Langdon J, et al.Br Dent J. 1991 Aug 10-24;171(3-4):87-90. doi: 10.1038/sj.bdj.4807616.Br Dent J. 1991.PMID: 1888588
Langdon JD, Leigh IM, Navsaria HA, Williams DM.Langdon JD, et al.Lancet. 1990 Jun 16;335(8703):1472-3. doi: 10.1016/0140-6736(90)91509-9.Lancet. 1990.PMID: 1972251No abstract available.