R. Albrektienė, M. Rimeika, E. Zalieckienė, V. Šaulys, and A. Zagorskis, “Determination of organic matter by UV absorption in the ground water”, JEELM, vol. 20, no. 2, pp. 163–167, Jun. 2012, doi: 10.3846/16486897.2012.674039.