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Bill A, Sperber GO.Bill A, et al.Graefes Arch Clin Exp Ophthalmol. 1990;228(2):124-7. doi: 10.1007/BF00935720.Graefes Arch Clin Exp Ophthalmol. 1990.PMID: 2338249
Roos MW, Sperber GO, Johansson A, Bill A.Roos MW, et al. Among authors: bill a.Exp Neurol. 1996 Jan;137(1):73-80. doi: 10.1006/exnr.1996.0008.Exp Neurol. 1996.PMID: 8566214
Törnquist P, Alm A, Bill A.Törnquist P, et al. Among authors: bill a.Eye (Lond). 1990;4 ( Pt 2):303-9. doi: 10.1038/eye.1990.41.Eye (Lond). 1990.PMID: 2199237Review.