Internal links in rmarkdown don't work

Question

I use rmarkdown to render pdf documents. Now I want to add internal links in the texts.

In the helping pages of rmarkdown, it says an internal link is defined as:

See the [Introduction](#introduction).

When I Use e.g. the next code there should be two internal links: link1 and link2. Both don't link. Is there something obvious that I am doing wrong? Many thanks in advance!

   ---
title: "Test"
author: "test test"
output:
  pdf_document:
    latex_engine: xelatex
    number_sections: yes
    toc: yes
    toc_depth: 3
  html_document:
    css: tables.css
    number_sections: yes
    theme: cerulean
    toc: yes
    toc_depth: 3
subtitle: test test test
mainfont: Calibri Light
fontsize: 12pt
header-includes:
- \usepackage[dutch]{babel}
- \usepackage{fancyhdr}
- \pagestyle{fancy}
- \fancyfoot[LE,RO]{this is a fancy foot}
- \usepackage{dcolumn}
- \usepackage{here}
- \usepackage{longtable}
- \usepackage{caption}
- \captionsetup{skip=2pt,labelsep=space,justification=justified,singlelinecheck=off}
---

# start

```{r results="asis",tidy=FALSE,eval=TRUE,echo=FALSE,message=FALSE, error=FALSE, warning=FALSE, comment = NA}
cat("click here: [link1](#test 1)")
```

click here: [link2](#test 1)

\pagebreak

#test 3

\pagebreak

#test 2

\pagebreak

#test 1

Answer 1

You're not setting the anchors correctly.

Try the following:

# start

```{r results="asis",tidy=FALSE,eval=TRUE}
cat("click here: [link1](#test1)")
```

click here: [link2](#test1)

\pagebreak

# test 3 {#test3}

\pagebreak

#test 2 {#test2}

\pagebreak

#test 1 {#test1}