HP 3000 and MPE/iX manuals might be found anywhere these days. It's a common request to hear from a 3000 pro, "Where can I find that manual?
HP is back in this business with a new interface. These webpages at HPE's website are a high-value address to locate documentation and make it available to a new 3000 administrator. Or a migration team trying to understand how something like TurboStore/iX works.
There's no guarantee of how long HP Enterprise will keep this library open. Get it while you can.