Yes, there is. That is why an *artifact* - a given
*hardcopy* of a
manual - has a *publisher*. As I mentioned in an earlier reply at some
point to someone, a given manual applies to a single machine
*manufacturer* (e.g., Apollo is considered the manufacturer of the DN
series, even though, technically, later HP made them for a year or two), but a
given manual with the same number the applies to them might have Apollo
as a publisher (older copy) and HP (newer copy - with the same contents).
A given hardcopy of a manual could not change publishers. The publisher is
permanent characteristic of that copy.
MOST attributes can change over time as new information comes to light. So for example I
also follow one of the Slide Rule forums and new information as to who actually
"Made" rather than "Sold" a particular rule all the time. Even the
I could conceivably add a Publisher column to the
Manual_File table, too
(indicating the publisher of that scan of the manual), but I didn't see the
point. Most textual searches in the online application will be on a join of
Manual and Manual_Artifact (where the Manual table data gets replicated in
the result set for each artifact), so the publisher can be picked up that way.