Rota-Baxter coalgebras and Rota-Baxter bialgebras
  We give a construction of Rota-Baxter coalgebras from Hopf module coalgebras and also derive the structures of the pre-Lie coalgebras via Rota-Baxter coalgebras of different weight. Finally, the notion of Rota-Baxter bialgebra is introduced and some examples are provided. 
Tianshui Ma and Linlin Liu
math.RA