1. A method for extracting referential keys from a document, the method comprising: parsing the document to identify at least one key, the key being identified from at least one indicator; classifying the key according to a key type, the key type being identified from the at least one indicator; extracting the key; and storing the key in a location in a structured shell, the location corresponding to the key type such that the key can be found by a search seeking at least one of the key and the key-type allowing a searcher to identify the document from which the key was extracted.