RMarkdown: How to change headline in table of contents in R Markdown?

Question

When I\'m using the toc: yes command, the document contains \"Content\" as the headline of the table of contents. Due to the fact that I want to write this document

Answer 1

With this YAML header that includes LaTeX-Package babel, it works for me:

---
title: "TOC in German"
header-includes:
  - \usepackage[ngerman]{babel}
output: 
  pdf_document:
    toc: true
    number_sections: yes
---