Best bookmark ever for a referee book

I’ve been looking for referee books and found Bewegend, Merk & More about experiences of German retired match official Markus Merk. It has the best bookmark ever (at least for a referee book): a yellow card

I still have to read it, but just wanted to show you. Recently I also found out the Royal Library in The Hague (where I live) had pretty much refereeing books in different languages. I’m very interested in them, so please tell me about good referee books you’ve read or heard about.

Bewegend, Merk & More about Markus Merk