Man pages matching name mail::box::imap4::head in section 3pm:

Mail::Box::IMAP4::Head.3pm.en	debian 10 / libmail-box-imap4-perl
Mail::Box::IMAP4::Head.3pm.en	debian 11 / libmail-box-imap4-perl
Mail::Box::IMAP4::Head.3pm.en	debian 12 / libmail-box-imap4-perl