I am writing a report with R Sweave and I would like to cite papers. It is the first time I use Sweave, but in Latex alone I used to call my bibliography with biblatex. Therefore, I'm calling the .bib file placed in the folder where my .Rnw file is.
Here's my code :
\documentclass[11pt, twocolumn]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[backend=biber]{biblatex} 
\addbibresource{references.bib}
\begin{document}
\SweaveOpts{concordance=TRUE}
test : \cite{helpman_globalization_2016}
\printbibliography
\end{document}
and here's the paper I want to cite (placed in references.bib) : 
@article{helpman_globalization_2016,
  langid = {english},
  title = {Globalization and {{Wage Inequality}}},
  url = {http://www.nber.org/papers/w22944.pdf},
  number = {22944},
  journaltitle = {NBER Working Paper Series},
  urldate = {2019-01-24},
  date = {2016},
  author = {Helpman, Elhanan},
  doi = {10.3386/w22944}
} 
I searched in several links but I couldn't find a solution :
https://tex.stackexchange.com/questions/71565/knitr-and-biblatex
https://texblog.org/2013/08/20/rknitr-automatic-bibliography-generation-with-biblatex-in-rstudio/
With knitr and .Rnw for LaTeX, how do you print the full bibliography in PDF output?
I also tried with backend = bibtex but it didn't work.
Here are the lines of the log describing the problem (I think) :
LaTeX Font Info:    ... okay on input line 8.
Package biblatex Info: Input encoding 'utf8' detected.
Package biblatex Info: Automatic encoding selection.
(biblatex)             Assuming data encoding 'utf8'.
Package biblatex Info: Input encoding 'utf8' specified.
Package biblatex Info: Data encoding 'utf8' specified.
(biblatex)             No need to reencode data.
\openout3 = `test_biblio-blx.bib'.
Package biblatex Info: Trying to load bibliographic data...
Package biblatex Info: ... file 'test_biblio.bbl' not found.
No file test_biblio.bbl.
Does anybody have a solution ?
Also asked here : https://community.rstudio.com/t/impossible-to-cite-with-biblatex-in-r-sweave/35008