1. Comparison of laboratory methods for predicting the organic matter digestibility of forages;Aerts;Anim. Feed. Sci. Technol.,1977
2. Agricultural and Food Research Council's (AFRC), 1993. Energy and Protein Requirements of Ruminants. An advisory manual prepared by the AFRC Technical Committee on Responses to Nutrients. CAB International, Wallingford, UK, 159 pp.
3. Anonymous, 1987. Alimentos para animais. Determinação do teor em amido. Método polarimétrico. Norma Portuguesa. NP 2026 (in Portuguese).
4. Association of Official Analytical Chemists (AOAC), 1990. Official Methods of Analysis. 14th edn., Vol. 1, AOAC, Washington DC, USA, 684 pp.
5. The use of the rumen degradation characteristics of hay as predictors of its voluntary intake by sheep;Carro;Anim. Prod.,1991