Man pages matching name poe::component::pubsub in section 3pm:

POE::Component::PubSub.3pm.en	debian 10 / libpoe-component-pubsub-perl
POE::Component::PubSub.3pm.en	debian 11 / libpoe-component-pubsub-perl
POE::Component::PubSub.3pm.en	debian 12 / libpoe-component-pubsub-perl