<https://www.farukerdem.com/postgresql-delete-trigger-nedir-nasil-kullanilir/2021/02/16#webpage>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<http://www.farukerdem.com/postgresql-delete-trigger-nedir-nasil-kullanilir/2021/02/16>