Patent ID: 8600942

Claim:
A method of relating documents, the method comprising: providing in a memory a first table-of-contents (TOC) data structure that includes a plurality of parent nodes and a plurality of child nodes, each child node being associated with one parent node to define a parent-child node pair for each combination of each child node and one parent node, and each child node further being associated with a document identifier that uniquely identifies a document in a document collection; defining in the memory a second TOC data structure that includes a plurality of relationship records, each relationship record including a parent-child node pair of the first TOC data structure, a unique identifier that uniquely identifies a relationship of the parent-child node pair of the first TOC data structure, and a time range associated with the unique identifier; and generating a hierarchical representation of a portion of the first TOC data structure based on identification of a time, the hierarchical representation excluding a parent-child node pair of a relationship record that has a unique identifier in the second TOC data structure associated with the time range that does not encompass the time.