1. Solution of a system of differential equations occurring in the theory of radioactive transformations;Bateman;Proc. Cambridge Philos. Soc., Math. Phys. Sci.,1910
2. S. Chałupnik, J. Lebecka, Determination of Ra-226, Ra-228 and Ra-224 in water and aqueous solutions by means of liquid scintillation counting, Advances in Liquid Scintillation Spectroscopy, Radiocarbon, Tuscon, AZ, 1993.
3. Natural radioactivity in drinking underground waters in Upper Silesia and solid wastes produced during treatment;Chmielewska;Appl. Radiat. Isot.,2014
4. Simultaneous determination of 226Ra and 238U in soil and environmental materials by gamma spectrometry in the absence of radium progeny equilibrium;Dowdall;J. Radioanal. Nucl. Chem.,2004
5. EC, Radiation protection 112. Radiological Protection Principles concerning the Natural Radioactivity of Building Materials. Directorate-General. Environment, Nuclear Safety and Civil Protection, 1999.