1. Investigation on blood groups of the pig;Andresen;Nordisk Veterinuermedicin,1957
2. Blood groups in pigs;Andresen;Annals of the New York Academy of Sciences,1962
3. Minus-minus (-l-) EaEd phenotypes and new allele Eeg (-E7) in pigs of the Hampshire breed;Andresen;Vox Sanguinis,1965
4. The E blood group system of the pig. I;Andresen;Nordisk Veterinaermedicin,1959
5. The E blood group system of the pig. II;Andressen;Nordisk Veterinaermedicin,1959