List of best mirrors for IP address 3.145.138.21, located in an unknown country.
I am very sorry, but no mirror was found. Feel free to download directly:
http://mirrordirector-mb.raspbian.org/raspbian/pool/main/libg/libgnatcoll-db/libgnatcoll-sqlite21-dev_23.0.0-4_armhf.deb