In your library or in a group library? If in your library, the most likely explanations are either:
They were added by someone other than you on a shared machine
They were added by you, but perhaps not intentionally (either because you imported the wrong file or a translator isn't working as it should or a site is providing bad metadata)
There were 578 references that have added. I believe some appeared when I added a journal article reference which was a review of many articles. I think it added all the references the journal article cited.
It is in a group library, but I checked with my group. the articlecs are not relevant to our work. Here is an example, library catalog field is empty.
Type Journal Article
Author M. Abe
Author J. Yaviong
Author G. Taleo
Author K. Ichimori
URL http://dx.doi.org/10.1016/S0035-9203(03)80004-4
Volume 97
Publication Trans R Soc Trop Med Hyg
Date 2003
Journal Abbr Trans R Soc Trop Med Hyg
DOI 10.1016/S0035-9203(03)80004-4
Date Added 13/02/2016 18:59:29
Modified 26/03/2016 09:42:11
Very helpful to look at added by. But it just says me. So when I added one reference I got an additional 578. I'm guessing that sometimes there is an option to add not just the journal ref of interest but also all the refs it cites?
typically not without asking (and not when it's working correctly). The fact that this doesn't have a library catalog entry, though, suggests that you imported a data file rather than directly from the web (e.g. a pubmed XML file or an RIS fiel from a publisher.
edit: yeah, see noksagt's question below. If you have an answer to that, we can almost certainly figure out what happened.
OK I think it was this one
http://parasitesandvectors.biomedcentral.com/articles/10.1186/1756-3305-5-69
On closer inspection I think it has an export citations choice that exports all. But the article only has 36 citations.
However, if this is common, I could have done it more than once
If in your library, the most likely explanations are either:
It is in a group library, but I checked with my group. the articlecs are not relevant to our work. Here is an example, library catalog field is empty.
Type Journal Article
Author M. Abe
Author J. Yaviong
Author G. Taleo
Author K. Ichimori
URL http://dx.doi.org/10.1016/S0035-9203(03)80004-4
Volume 97
Publication Trans R Soc Trop Med Hyg
Date 2003
Journal Abbr Trans R Soc Trop Med Hyg
DOI 10.1016/S0035-9203(03)80004-4
Date Added 13/02/2016 18:59:29
Modified 26/03/2016 09:42:11
edit: yeah, see noksagt's question below. If you have an answer to that, we can almost certainly figure out what happened.
http://parasitesandvectors.biomedcentral.com/articles/10.1186/1756-3305-5-69
On closer inspection I think it has an export citations choice that exports all. But the article only has 36 citations.
However, if this is common, I could have done it more than once