20140728.json.gz is not very explicative, all the other dumps have some sort of prefix. Something like wikidatawiki-, or even wikidatawiki-external- or whatever to give info on format as well, would be best.
Version: unspecified
Severity: enhancement
URL: https://dumps.wikimedia.org/other/wikidata/
See Also:
https://bugzilla.wikimedia.org/show_bug.cgi?id=70385