@InProceedings{LiLuMi-DL-08,
  author = 	 {Hongkai Liu and Carsten Lutz and Maja Milicic},
  title = 	 {The Projection Problem for $\mathcal{EL}$ Actions},
  booktitle = {Proceedings of the 2008 International Workshop on Description Logics ({DL2008})},
  year = {2008},
  series = {CEUR-WS},
  volume = {353}
 }