I'll do some...these are more relaxing than Solitaire!
It got easier once I figured out to "tease them apart" (put the cursor between a close </ref> tag and the following <ref> open ref tag....and add some returns to get some space. That helps see the typos, incorrect tag, and other kinds of errors.
It also helps find the extra, unneeded, open or closed tags which will result in an error.
Once fixed, just take the extra returns back out and close up the block of text.