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Shortridge KF, Butterfield WK, Webster RG, Campbell CH.Shortridge KF, et al. Among authors: campbell ch.Bull World Health Organ. 1979;57(3):465-9.Bull World Health Organ. 1979.PMID: 314357Free PMC article.
Shortridge KF, Butterfield WK, Webster RG, Campbell CH.Shortridge KF, et al. Among authors: campbell ch.Bull World Health Organ. 1977;55(1):15-20.Bull World Health Organ. 1977.PMID: 302152Free PMC article.
Butterfield WK, Campbell CH, Shortridge KF.Butterfield WK, et al. Among authors: campbell ch.Proc Annu Meet U S Anim Health Assoc. 1978;(82):325-31.Proc Annu Meet U S Anim Health Assoc. 1978.PMID: 287100No abstract available.
Butterfield WK, Campbell CH.Butterfield WK, et al. Among authors: campbell ch.Proc Annu Meet U S Anim Health Assoc. 1978;(82):320-4.Proc Annu Meet U S Anim Health Assoc. 1978.PMID: 287099No abstract available.