@incollection{NIPS2005_818,
 title = {Combining Graph Laplacians for Semi--Supervised Learning},
 author = {Andreas Argyriou and Mark Herbster and Massimilano Pontil},
 booktitle = {Advances in Neural Information Processing Systems 18},
 editor = {Y. Weiss and B. Sch\"{o}lkopf and J. Platt},
 publisher = {MIT Press},
 address = {Cambridge, MA},
 pages = {67--74},
 year = {2006}
}