A method of storing information for recorded information and a source document is provided. The method comprises: determining a first piece of information included in the recorded information; determining at least a first source document from one or more source documents that comprises information that matches the first piece of information; and storing information identifying the recorded information, information representative of the first piece of information, and information identifying the first source document such that the information identifying the first source document can be determined given the information identifying the recorded information and the information representative of the first piece of information.