1. A multiple citation corpus data structure stored in a computer memory for a user specified word or phrase comprising an entry for every occurrence of the user specified word or phrase, each entry comprising: a) prior context, b) the user specified word or phrase, c) subsequent context, and d) one or more internal citations, wherein the prior context, the user specified word or phrase, and the subsequent context forming a unique quote of each entry, wherein each internal citation identifies a document and the location inside the document where the unique quote of the entry is found in a plurality of formatted documents, and wherein the one or more internal citations of each entry is a combined citation comprising a complete list of every occurrence of the unique quote of the respective entry in the respective plurality of formatted documents.