You can tell TeX to typeset a document for printing on European size
A4 paper with the @afourpaper command. Write the command on a
line by itself between @iftex and @end iftex lines near
the beginning of the Texinfo file, before the title page:
For example, this is how you would write the header for this manual:
\input texinfo @c -*-texinfo-*- @c %**start of header @setfilename texinfo @settitle Texinfo @syncodeindex vr fn @iftex @afourpaper @end iftex @c %**end of header