I need a help from you. Can you provide me the list of work products needed to achieve CMMI in our organization?
Let me ask you this. Should you reach your destination in a car by looking at the white line in the road through your rear-view mirror?
This kind of "reverse engineering" of the CMMI was never really intended by the authors. The documents you are referring should be the product produced from performing a process.
So, if you conduct an estimate using "wide-band delphi" the work products, or "documents," you produce may include the three or more estimates developed by the assigned estimators, the list of tasks in a WBS, and the output of the formal estimate.
If I said, go produce an estimate, you might just sit at your desk and type one up without executing the process. But you would have "the document." Does that mean you performed the process? No, it means you typed in your best guess of the estimate. And it definitely doesn't mean your CMMI ML2.
The CMMI does expect you to produce a "direct artifact" and an "indirect artifact" (in most cases). This is not the same as saying that all you need is the artifact. They are merely a consequence of the process being performed. You must also produce evidence that you actually followed a process.
There is a list of "suggested work products" in the CMMI book that you COULD use as a guide, but this list is highly dependant upon your company, methodology, and culture.