Test file field

gipp.bib

@@ -940,7 +940,6 @@
   booktitle = {Intelligent Computer Mathematics - 10th International Conference, {CICM} 2017, Edinburgh, UK, July 17-21, 2017, Proceedings},
   date      = {2017},
   doi       = {10.1007/978-3-319-62075-6_9},
-  file      = {Cohl17.pdf:pdf/Cohl17.pdf:PDF;Cohl17.pdf:Cohl17.pdf:PDF},
   keywords  = {schubotzCV},
   pages     = {115--131},
   series    = {Lecture Notes in Computer Science},
@@ -1227,6 +1226,7 @@
   booktitle = {Proceedings of the International ACM SIGIR Conference on Research and Development in Information Retrieval (SIGIR)},
   date      = {2018},
   doi       = {10.1145/3209978.3210177},
+  file      = {Meuschke2018a.pdf:Meuschke2018a.pdf:PDF},
   keywords  = {SchubotzCV},
   preprint  = {https://www.gipp.com/wp-content/papercite-data/pdf/meuschke2018a.pdf},
   title     = {HyPlag: A Hybrid Approach to Academic Plagiarism Detection},