_output.yml

bookdown::gitbook:
  css: style.css
  config:
    toc:
      before: |
        <li><a href="./">Global Health Research: Data Science</a></li>
      after: |
        <li><a href="http://www.designsandmethods.com/" target="blank">Eric P. Green</a></li>
    edit: https://github.com/ericpgreen/GHDS/edit/master/%s
    download: ["pdf", "epub"]
bookdown::pdf_book:
  includes:
    in_header: preamble.tex
  latex_engine: xelatex
  citation_package: natbib
  keep_tex: yes
bookdown::epub_book: default