4. The method of claim 1 , wherein at least one of the different queries is configured to score a reference document based on the reference document's relevance with respect to the source document.
4. The method of claim 1 , wherein at least one of the different queries is configured to score a reference document based on the reference document's relevance with respect to the source document. 5. The method of claim 4 , wherein the at least one of the different queries is further configured to score the reference document based on a number of reference documents identified in the at least one query's respective list of documents.