`r if (knitr:::is_html_output()) '# References {-}'`

```{r include=FALSE}
pkgs <- c('granova', 'granovaGG', 'Matching', 'MatchIt', 'mice', 
          'multilevelPSA', 'party', 'PSAboot', 'PSAgraphics', 'rbounds',
		  'TriMatch', 'GGally')
knitr::write_bib(c(
  .packages(), 'bookdown', 'knitr', 'rmarkdown', pkgs
), 'packages.bib')
```
