Low-rise rear rack for 20" wheel bike?

Hello,

I just got an Orbea Katu 20 (https://www.orbea.com/int-en/bicycles/katu-20-18):

Image: https://s17.postimg.org/3xbypwpwf/Orbea.Katu.20.silver.png

As you can see, it's not a folder, but since it sports 20" wheels, I figure someone here might now.

I'd like to add a rear rack that...