@inbook{OB2008,
author = {A. Orriols-Puig and  E. Bernad\'o-Mansilla},
title = {Revisiting UCS: Description and  Fitness Sharing and  and Comparison with XCS},
booktitle = {Advances at the frontier of LCS},
publisher = {Springer},
pages = {96--116},
year = {2008}
}