Man pages matching name math::bigint::gmp in section 3pm:

Math::BigInt::GMP.3pm.en	debian 10 / libmath-bigint-gmp-perl
Math::BigInt::GMP.3pm.en	debian 11 / libmath-bigint-gmp-perl
Math::BigInt::GMP.3pm.en	debian 12 / libmath-bigint-gmp-perl