Gobipteryx isn't the only Late Cretaceous Mongolian bird. Chatterjee mentions Gobipipus reshetovi, a neornithine from the Barun Goyot Formation known from eggs (with neognath eggshell) containing precocial embryos ready to hatch.
Additionally, there are enantiornithine eggs known from that formation.
Sankar Chatterjee: The Rise of Birds. 225 Million Years of Evolution, Johns Hopkins 1997
David Marjanovic, new member (Hi everyone) from Austria (that §"%§&($)(/%!"(§$%!!!Haider country, not Australia)
P.S.: Please tell me whether you can see the italics and bold (I'm writing in Outlook Express) and the c with accent (´) at the end of my name.