Caption for a figure reproduced from a CC-licensed document
Including the license terms in the figure caption isn't necessary.  "Attribution" in CC licensing is usually interpreted as "provides name of author and/or source of original", which you do fine with just "Reference X".

EDIT from comments: As pointed out by @ff524, the CC guidelines suggest including license terms. It makes sense to include title, author name, source, license in the reference section.  Not necessary for the image caption though.