# Academia Científica5 Footnotes and citations

## 5.1 Footnotes

Footnotes are put inside the square brackets after a caret ^[]. Like this one 1.

## 5.2 Citations

Reference items in your bibliography file(s) using @key.

For example, we are using the bookdown package (Xie 2022) (check out the last code chunk in index.Rmd to see how this citation key was added) in this sample book, which was built on top of R Markdown and knitr (Xie 2015) (this citation was added manually in an external file book.bib). Note that the .bib files need to be listed in the index.Rmd with the YAML bibliography key.

The RStudio Visual Markdown Editor can also make it easier to insert citations: https://rstudio.github.io/visual-markdown-editing/#/citations

### References

Xie, Yihui. 2015. Dynamic Documents with R and Knitr. 2nd ed. Boca Raton, Florida: Chapman; Hall/CRC. http://yihui.org/knitr/.
———. 2022. Bookdown: Authoring Books and Technical Documents with r Markdown. https://CRAN.R-project.org/package=bookdown.

1. This is a footnote.↩︎