Touch Shelves

[ebookskippy]

Please excuse the spelling and grammatical errors but this is not my native language.
As you can see I am relatively new to this forum and and a great "Thanks" to the members for their tips and hints.

I have organized my shelves on the kobo in this manner / form

{series:'ifempty($, field('#genre'))'}

and I'm (almost) happy with it.

My wish: A prefix like SER or GEN for identifikation.
I tried many things but there was no solution.
Is that even possible?
Thanks for any advice -P-