This sentence occurs in an (Austrian) tender document:
Nur falls der Bieter kein elektronisch signiertes Angebot abgeben kann, darf das Angebot in Papierform bei der angeführten Postadresse der vergebenden Stelle [einlangend!] einzureichen.
As far as I know, 'einlangend' is normally used to make sure that the given date/time is understood as the date/time the thing is supposed to arrive, not the date/time the thing is posted. (e.g. mail, bank transfer, ...)
However, in this case there's no date given anywhere.
Now, assuming they didn't merely make a mistake in the document (leaving in 'einlangend' but removing the deadline, or forgetting to put in the deadline, for example), and given the importance of the document, my suspicion is that they may be using 'einlangend' to specify the type of mail (registered mail / Einschreiben).
This sound plausible to any of you (especially Austrians)?
Help a piefke out, will you? ;)