5.1 Error: Failed to build the bibliography via biber

This can happen if you’ve had a failed build, perhaps in relation to RStudio shutting down abruptly.

Try doing this:

1. type make clean-knits in the terminal tab (or run file.remove(list.files(pattern = "*.(log|mtc|maf|aux|bbl|blg|xml)")) in the R console) to clean up files generated by LaTeX during a build
2. restart your computer

If this does not solve the problem, try using the natbib LaTeX package instead of biblatex for handling references. To do this, go to index.Rmd and

1. set use-biblatex: false and use-natbib: true
2. set citation_package: natbib under

output:
  bookdown::pdf_book:
    citation_package: natbib