With the value "index=numbered" within the document class "scrbook" I changed the chapter head in this example from "MyIndex" to "2 MyIndex". In the pagehead
Command/setuphead - Wiki
Command/setuphead - Wiki
openscraping-lib-csharp/OpenScraping.Tests/TestData/stackoverflow
How to import a header and footer in HTML - Quora
Section and chapters overlap with header page numbers - TeX
How to set page number at right footer - TeX - LaTeX Stack Exchange
Headers and footers - Overleaf, Online LaTeX Editor
Problem with header, footer and page number - TeX - LaTeX Stack
The memoir class - The UK TeX Archive
Changing only the header for Table of Contents pages with package
Command/setuphead - Wiki
fancyhdr resets geometry to adjust header heights? - TeX - LaTeX
The Stata-to-LaTeX guide. The guide provides a set of templates
