Sub-referencing work from the referenced work Sorry for the tricky title. I am working on a (IEEE) conference paper and in the related work section I have sentence that goes like this:

In [X], the authors derive YYY metric from the Gov. Institution Name's Obscure Parameters Database. Should I put a reference after the "Obscure Parameters Database"? My understanding is that whoever is interested - will be able to find it wither by looking up the [X] work or by searching the Internet for the database (it is open to the public). Am I correct?
Cite the database, and in citing it and/or in context, provide a way for your audience to know which version or part of the database was used. Ideally, you should provide sufficient details for your audience to know how the authors of work [X] produced their metric.