1. Range and Error of Densitometers for Emission Spectroscopy
2. Calder A. B. and Voss R. C. “The Sampling of Hill Soils and Herbage with Particular Reference to the Determination of the Trace Elements,” Bull. No. 1, (Consultative Comm. for Devel. of Spectrographic Work, Aberdeen, Scotland, 1957) pp. 16–30.
3. Sherman J., Physical Methods in Chemical Analysis, Berl W. G., Ed. (Academic Press Inc., New York, 1950), p. 327.
4. Zur Praxis der Seidel-Transformation
5. The Spectrographic Determination of Trace Elements Using a Three-Step Filter and the Respektra Calculator