I have several A4 PDF documents which I would like (two into one) \"glue\" together into A3 format PDF document. So I will get from 2PDFs A4 a single one si
On the Postscript side, a tool named pstops is able to rearrange pages of a Postscript file in any way you could imagine. I've not heard of such a tool for PDF. But pdf2ps and ps2pdf exist. So a not-so-ideal solution may be a combination of pdf2ps, pstops and ps2pdf.