Hi,
JabRef has no Importer for CSV, and the code in the example is outdated. However, it seem some other users managed to get it working again in this thread:
The biggest problem is that there is no true CSV format standard for bibtex as it simply depends on the format of the csv, e.g. how you structured it.
The easiest solution is to try manually/semi automatically use identifiers like DOI, Arxiv or PMID, ISBN etc. to get the bibtex data from it.
DOI would be the easiest option.
See this discusion for an example: Are there tools for importing from CSV to BibTeX? - TeX - LaTeX Stack Exchange