The double taxation agreement was concluded on 19 September 2011 between the Republic of Turkey and the Federal Republic of Germany. The DTA serves to regulate the extent to which a state is entitled to tax on the income generated in one of the two contracting states. The purpose of the agreement is to prevent natural or legal persons who generate income in both countries from being taxed twice – in both countries. You can get detailed information at: https://tuerkei.diplo.de/tr-de/themen/wirtschaft/-/1674324