Like this in the .tex file:

```
As trace gases stay for more than one week in the UT, they are distributed by the upper level winds around the globe \cite{Ridley.2004}.
```

I'm using the Sublime Text.

Here's the workflow:

1. Export all references in Zotero to one bib file called references.bib
2. Cite the bib file in the journal template (tex file):
\bibliography{references}
and cite it by typing \cite{} as I use better BibTeX.
3. Compile the PDF file.

I want to export only the references used in the tex file to the bib file.
In this case, it is {Ridley.2004}.
It could decrease the bib filesize a lot.

Thanks. The problem is that I have to create a new collection and copy references to that collection. Is it possible to inverse these used references in Zotero and save them into a new collection?

With BBT, you can use AUX files for creating Zotero collections that contain your cited entries:
https://forums.zotero.org/discussion/77365/create-bib-file-only-from-papers-cited-in-a-tex-file
https://retorque.re/zotero-better-bibtex/citing/aux-scanner/

AUX files are generated when compiling LaTeX documents, see here. Your BibTeX tool might be able to use them for creating .bib files with your cited entries.

If you have further questions specifically on LaTeX/BibTeX, consider asking for help here: https://tex.stackexchange.com/

Thanks all!

Finally, I use the aux scanner and follow the tutorial below to export the subcollection as bib file successfully ;)

https://forums.zotero.org/discussion/28227/how-do-i-export-a-subset-of-my-library-to-bibtex