@INPROCEEDINGS{crvm-lopstr11,
 author    = {Rafael Caballero and
              Adri\'an Riesco and
              Alberto Verdejo and Narciso Mart\'{\i}-Oliet},
 title = {{Simplifying Questions in Maude Declarative Debugger by Transforming Proof Trees}},
 booktitle = {LOPSTR 2011},
 year = {2011},
 series = {LNCS},
 publisher = {Springer-Verlag},
 volume   = {7225},
 pages = {73-89}
}