Identifying layer file within a worksession

We’ve just started using worksessions in the office and are currently struggling with layers.

I will give an example of our problem as it might be easier to explain and understand: we use the same set of layers (same names) in all our files when we are drawing. So for example, in a worksession we will have a file named Plan with layers H, HB, B, BB. We will also have a file named Section A with same layer names and a file named Section B using the same layer names. If I’m working in file Plan and select a curve that is not on my active file how can I identify in which file it is saved? I can see which layer it is in but how do I know to which file that layer belongs to?

Many thanks