Need help finding error

[Rich Shepard]

I've not successfully built a MWE; each time I remove text either above or
below the highlighted error the document compiles successfully. The
unmodified doc doesn't.

Attached is an image of the highlighted line and following text along with
the error reporting box, and the complete error log file. I do not see the
error there.

I need help identifying the source of this error. FWIW, the doc built
successfully before I added more text below where the error is shown.

TIA,

Rich
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