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2. Ibid.: 3. Traumatic injuries. Ibid. 1974, 26, 617–625.
3. Bäckström L: Environment and animal health in piglet production. A field study of incidences and correlations (thesis). Acta vet. scand. suppl. 41, 1973.
4. English PR, Morrison V: Causes and prevention of piglet mortality. Vet. Bull. 1984, 54, 369–376.
5. Halgaard C: Epidemiological factors in piglet diarrhoea. Nord. Vet.-Med. 1981, 33, 403–412.