printing A4 pages on A3 paper

[Federico Bruni]

Hi,

in a print shop I was told that they couldn't directly print my A4 .pdf
to A3 paper - using Adobe Reader - because in the pdf "pages are linked
two by two" (I guess they meant to say "twoside").

So they had to first print on A4 sheets and then use them to print on A3
paper.

Frankly speaking, I'm quite sure they are wrong and the problem is not
my pdf settings.
I compiled the book using the "Publish" button of Frescobaldi (lilypond
-dno-point-and-click) and \paper does not contain anything that changes
default paper settings.

Anyway, I missed an argument to reply to them :)
Can you give me a piece of advice?

I just want to be sure that my pdf is ok and understand why the shop
failed to print directly to A3.

Thanks,
Federico