Man pages matching name pmdalabel in section 3:

pmdaLabel.3.en	debian 10 / libpcp-pmda3-dev
pmdalabel.3.en	debian 10 / libpcp-pmda3-dev
pmdaLabel.3.en	debian 11 / libpcp-pmda3-dev
pmdaLabel.3.en	debian 12 / libpcp-pmda3-dev