Source: Häusler, J., S. Enzenhofer, B. Fürst-Waltl and A. Steinwidder (2015): Effects of different weaning dates on extensively fed Simmental cows and their calves 2. Communication: Development of young cattle in the suckling period and in the intensive fattening period. Breeding Science 6, 391–412.
The detailed research results of the HBLFA Raumberg-Gumpenstein can be found here: