Pandoc error parsing BibTeX file

I get this error so often (and I always forget how to solve it) that I thought I’d post a solution. Here’s the error: pandoc-citeproc: "stdin" (line 2421, column 2): unexpected "m" expecting "c", "C", "p", "P", "s" or "S" pandoc: Error running filter /usr/lib/rstudio/bin/pandoc/pandoc-citeproc Filter returned error status 1 Error: pandoc document conversion failed with error 83 The problem is that there’s an entry in my bibliography BibTeX file without a trailing comma: