Am 2007-05-03 um 21:19 schrieb Willi Egger:
Consider A4 which is portrait because of the grain direction (Laufrichtung) in the height. Otherwise A3 is two A4 and hence the grain direction is in the shorthand. - Generally speaking the graindirection is in the direction of the longer edge in all A- foomats with even numbers, including A0. - Looking in this way at RA3 and SRA3 I would expect that the graindirection is also on the short side. Therefore The definition shoud be width=305 and height=430 mm and width=320 and height=450mm respectively.
So Luigi you learned determination of the grain direction in Epen, please look this up in your two blocks!
Kind regards Willi, the bookbinder ;-)
As a bookbinder you should know that you can get paper in both grain directions (even if one's much more usual).
ISO definitions of paper sizes are always portrait.
see also http://wiki.contextgarden.net/PaperSizes I never heard of RA/SRA sizes before (doubt that they're standardized), but feel free to add them as soon as the wiki has moved.