Haku
Viitteet 1-2 / 2
Wood, bark, peat and coal ashes as liming agents and sources of calcium, magnesium, potassium and phosphorus
(Agricultural Research Centre, 1991)
The dependence of yield increases obtained with phosphorus and potassium fertilization on soil test values and soil pH
(Agricultural Research CentreMaatalouden tutkimuskeskus, 1980)