»Tax Procedural Internum of the Taxpayer? Scope of the Taxpayer's Obligation to Cooperate with Regard to Internal Tax Documents Prepared Without Legal Obligation«: In principle, the tax authority has to determine the tax-relevant facts of each individual taxpayer. However, the respective information relevant for taxation regularly materializes in the sphere of the taxpayer, which is why he is obliged to cooperate. The thesis examines the extent to which the tax authorities can demand the submission of internal tax documents from the taxpayer that have been prepared without a legal obligation. For this purpose, it develops the institute of the tax procedural internum, which, as a movable system, leads under certain circumstances to the restriction of the taxpayer's obligation to submit documents.weiterlesen