1. Bäckström L: Environment and animal health in piglet production. A field study of incidence and correlations. Acta vet. scand. suppl. 41, 1973.
2. Bäckström L, Einarsson S, Gustafsson B, Larsson K: Prostaglandin F2 alpha induced parturition for prevention of the agalactia syndrome in the sow. Proceed. 4th. Inter. Pig. Vet. Soc. Cong. Ames, Iowa, USA 1976, E. 5.
3. Einarsson S, Gustafsson B, Larsson K: Prostaglandin induced parturition in swine with some aspects on prevention of the MMA (mastitis, metritis, agalactia) syndrome. Nord. Vet.-Med. 1975, 27, 429–436.
4. Elmore RC, Martin CE, Riley JL, Littledike T: Body temperature of farrowing Swine. J. Amer. Vet. Med. Assoc. 1979, 174, 620–622.
5. Elmore RG, Martin CE: Mammary Glands in Diseases of Swine. 6th Ed., Iowa University Press, Ames, Iowa, USA 1986.