O. Iismaa

The determination of chromic oxide in faeces samples by atomic absorption spectrophotometry

C. Williams, D. J. David, O. Iismaa, 1962, The Journal of Agricultural Science.

Determination of total sulphur in soil and plant material

O. Iismaa, N. Barrow, A. Steinbergs, 1962 .

The determination of cadmium in soils, plants and fertilizers by dithizone extraction and atomic absorption spectroscopy

C. Williams, D. J. David, O. Iismaa, 1972 .