1. Anonymous (1998) NEN 7432 Manure and derivatives. Determination of the contents of dry matter and organic matter. Gravimetric method. Dutch Standardization Institute (NNI), Delft, (in Dutch)
2. Atkins P, Jones L (1997) Chemistry molecules, matter and change, 3rd edn. Freeman, New York
3. Castellanos JZ, Pratt PF (1981) Mineralization of manure nitrogen—correlation with laboratory indexes. Soil Sci Soc Am J 45:354–357
4. Cerda AD, Manterola BH, Sirhan AL (1989) Comparative study and validation of three methods to estimate apparent digestibility of forages. Proceedings XVI international grassland congress, Nice, France, pp 901–902
5. Chescheir GM, Westerman PW, Safley LM (1986) Laboratory methods for estimating available nitrogen in manures and sludges. Agric Wastes 18:175–195. doi: 10.1016/0141-4607(86)90112-5