Olesiak, Jarosław. 2021. “Obligatio Naturalis in Tax Law? A Few Remarks on the Regulation of the taxpayer’s Liability in Face of Understating (not Reporting) the Tax Base by the Paying Agent”. Studia Prawno-Ekonomiczne 118 (May):59-74. https://doi.org/10.26485/SPE/2021/118/4.