Man pages matching name net::google::authsub in section 3pm:

Net::Google::AuthSub.3pm.en	debian 10 / libnet-google-authsub-perl
Net::Google::AuthSub.3pm.en	debian 11 / libnet-google-authsub-perl
Net::Google::AuthSub.3pm.en	debian 12 / libnet-google-authsub-perl