sure that you retrieved trusted and untampered software. GNU Privacy
Guard is used for that purpose.
-For the very first time it it necessary to get signing public key and
+For the very first time it is necessary to get signing public key and
import it. It is provided below, but you should check alternative
resources.
software. @url{https://www.gnupg.org/, The GNU Privacy Guard} is used
for that purpose.
-For the very first time it it necessary to get signing public key and
+For the very first time it is necessary to get signing public key and
import it. It is provided below, but you should check alternative
resources.