I have a .bib file filled with all the citation within the text. I need to use it in a template format (the IEEE Access). This template is used within Overleaf.

When inserting the lines:





I have this error:

! Undefined control sequence. l.77 \externalbibliography


  1. Can I use an external .bib file in a template where the other reference are within the .tex file?

  2. if so, which is the right \usepackage{...} to be included?

  • The solution in the comment does not work properly (maybe I did something wrong I guess) and other errors appear using IEEEtran. Is that format proper of another journal? The IEEE transaction should be the right target and not the IEEE access, isn't it? – Leos313 Dec 2 '19 at 11:24
  • thank you @KersouMan, I am going to investigate and I will let you know! thank you again – Leos313 Dec 2 '19 at 11:53


Asking my office colleague expert on IEEE Access, the solution is just adding these two lines:


Where my bib file is refs.bib. It works properly as it is. No other packages are needed.

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