I wouldn't worry too much about "detrimental" literature (unless it was something encouraging terrorism? *g*). I'd be more worried about the lack of the green form... If you sent it along with local packages, then the clerk at the post office might not notice that this one was being sent abroad. To the best of my knowledge, it is for the customs' information. I don't really know what they would do to a package without this info. Send it back?