References
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- Cameron , T. W. M. 1951 . The Parasites of Domestic Animals , 2nd Edn. , 105 – 105 . London : A. and C. Black .
- Dunne , E. H. 1958 . Diseases of Swine , 432 – 432 . U.S.A. : Iowa State College Press .
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- Mönnig , H. O. 1950 . Veterinary Helminthology and Entomology , 3rd Edn. , 208 – 208 . London : Baillière, Tindall and Cox .
- Nicolson , T. B. and Gordon , J. G. 1959 . Vet. Rec. , 11 : 133 – 133 .
- Shanks , P. L. 1963 . Vet. Rec. , 15 : 287 – 287 .