Relationship between the amount and the activity of the microbial biomass in dutch grassland soils : comparison of the fumigation-incubation method and the Substrate-induced respiration method J. Hassink text Ind Repr. from : Soil Biol. Biochem, Vol. 25(5) 1993 : p. 533-538 Bibl. : p. 538. Repr. from : Soil Biol. Biochem, Vol. 25(5) 1993 : p. 533-538 Bibl. : p. 538. SOIL BIOLOGY GRASSLANDS NETHERLANDS