I'm working on a book that uses tables and figures, but the editors want to use to diffferent captions for each figure: one as usual, with the float description and number, and another one with  a "Source" for said float.  Something like:

---------------------------------
|                               |
|           Float               |
|                               |
---------------------------------
Figure 1: The float description.
Source: The float source. 

I know i can do it by hand, inserting line breaks in the caption and so on. But I was wondering if there is a programmatic way to do it, so I can, for example, change the "Caption" position to be above the float, but have the "Source" below it. LIke:

Figure 1: The float description.
---------------------------------
|                               |
|           Float               |
|                               |
---------------------------------
Source: The float source.

I've been reviewing the Wiki, but so far I have no idea how to approach it.

Any recommendation will be very appreciated. Thank you for your time.

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