008_20902_1rar -

Which uses alphanumeric strings to track mission reports and diplomatic cables.

If you found this online, the URL path often contains the name of the institution (e.g., archives.org/collections/[Name]/008_20902_1rar ). 008_20902_1rar

Often appearing as "stamps" on the top of declassified documents. How to Investigate Further Which uses alphanumeric strings to track mission reports