It seems that VE is incorrectly handling references with an ISBN13 starting with 979.
For example, on frwiki, article Petrea volubilis, if I edit the article with VE, and try to add a reference with the "Sources" button (References), and input the first ISBN in the field for automatic reference and click Générer (Generate), the suggested reference contains 3 ISBN: 9782877631815, 9791029801 and 2877631818. The first and the third are correct, but the second is missing its last 3 digits. The dialog says that the values are coming from Worldcat, with OCLC 496442002, but Worlcat correctly displays the second ISBN as 9791029801297 (note the last 3 characters missing in the generated reference)
I've noticed a lot of article with ISBN13 starting with 979 truncated after the first 10 digits, and I've always wondered where it came from, I even asked some editors if they used some external tools to generate the references, but it seems that it's the internal Reference gadget that is truncating ISBN.