Man pages matching name libinn in section 3:

libinn.3.en	debian 10 / inn
libinn.3.en	debian 10 / inn2-dev
libinn.3.en	debian 11 / inn
libinn.3.en	debian 11 / inn2-dev
libinn.3.en	debian 12 / inn
libinn.3.en	debian 12 / inn2-dev