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I like the clean and short form, but unfortunately it doesn't work. To solve the problem I have been suggested to define a new header only for the appendix:

\documentclass[b5paper]{memoir}
\usepackage[utf8]{inputenc}
\usepackage{blindtext}

%%%%%%%%% HEADER AND FOOTER FORMAT %%%%%%%%%

\def ...

I am completing the template for my PhD thesis. Everything works as expected, except the appendix header :roll: .

So far, it only displays the title: " A Journal articles ".
What I want instead is: " Appendix A Journal articles ".

The document class is *memoir* and here is an MWE showing the ...