EDIT

It should be easy to add a reference (source) to the distribution status edited with Vaadin Editor.

We need a field to choose the default reference for (new?) status. This is because often when entering distribution data you work through one reference and enter all available data.

Additional we may add a reference search field in the status selection popup just below the status selection. This is to overwrite the default (or the existing) source.

We may also discuss other ways to do it (or implementing multiple sources editing), but this is a good starting point.