@inproceedings{p2015,
    title = {One Conference in 2015},
    booktitle = {Nikola Tesla Conference},
    author = {Nikola Tesla},
    year = 2015
}

@article{a2015,
    title = {One Article in 2015},
    author = {Nikola Tesla},
    year = 2015,
    journal = {Great Journal},
    volume = 1,
    page = {1--10},
    fulltext = {/pdf/a2015.pdf},
    abstract = {The abstract}
}

@inproceedings{p2015,
    title = {One Conference in 2015},
    booktitle = {Nikola Tesla Conference},
    author = {Nikola Tesla},
    year = 2015
}

Add tests for BibTeX entries with duplicated labels.
publication_list: Add tests for BibTeX entries with duplicated labels.
