List of best mirrors for IP address 18.189.143.150, 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/p/postfix-mta-sts-resolver/postfix-mta-sts-resolver_1.4.0-1_all.deb