NIST SP 800-57
NIST's recommendation for key management – the document that decides how long a key may live and how long it needs to be.
Part 1 first appeared in 2005 and has been revised several times, most recently as Rev. 5 in 2020. It is the general part: key types, their lifecycle from generation to destruction, cryptoperiods, and the tables of comparable security strength that tell you RSA-3072 is roughly worth 128 bits of symmetric strength. Part 2 is aimed at organisations, Part 3 at specific protocols and applications.
It is not light reading, but it is what auditors, FIPS validations and procurement documents point to whenever someone asks why a key has to be rotated. Anyone wondering why a key hierarchy looks the way it does will usually find the reasoning here.