Duffer:
I've seen it in an interview, when Duff was talking about his hungarian girlfriend, who dressed him up for those photos, which are on the cover of Live Era. I guess most of u have seen that interview. So when I first heard it, I realized that there's a hungarian name on the cover of AFD in the acknowledgements, Katalin Kerekgyarto.
After the concert in Budapest, I saw a short interview with Duff on TV, and he said, that when he moved to LA, his first girlfriend was hungarian, and he remembered her name! Ok, he didn't remember her surname, but he said that her name was Catherine /Katalin/. And he said, that he'd learnt some hungarian expressions, for example "rakottkrumpli" - it's a food which I don't know in English, "Hogy vagy?" - How are u?, and "Köszönöm szépen" - Thank u very much. It was so funny and cool to hear these things from Duff, with his accent.