Silver Books: Historical - Obsolete
CCSDS Historical designation (Silver Books) is reserved for any approved CCSDS document that has been superseded by a more
recent version or is for any other reason considered to be obsolete. More often than not, a CCSDS Historic document will be a CCSDS Recommended
Standard that has come to the end of its useful operational life and no longer controls a committed deployment of international CCSDS-compatible
mission support infrastructure.