Merge multiple pdfs while keep the links working ([from SO](https://stackoverflow.com/a/19358402/2886003)): ``` gs -q -SDEVICE=pdfwrite -DPDFSETTINGS=/prepress -o merged.pdf ~/Documents/PhD/Defensa/Primera_plana_Tesi_Lluís_Revilla.pdf ~/Documents/PhD/Defensa/Segona_plana_Tesi_Lluís_Revilla.pdf 20220404_submission_thesis_Lluis_Revilla.pdf ```
