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When managing References, seem to me to be two-ish, options:
Either for each Project, I maintain a database of the relevant resources (In say a bibtex file), and for each new piece of work I start a new one.
Or I maintain a single "Monolithic" collection of resources (still in a bibtex file), for everything I do, and I carry that around with me for years.
There are some in-betweens, such as having a Monolithic Collection, which I copy references from at the start of a project into a Project Collection, which I then use (and update) during the project, then copy either all or some of it back into the main collection.
What are the Pros and Cons of each approach? Am I thinking about this in the wrong way?