18. The computer system of claim 11 , further comprising computer-readable instructions that when executed by the processor cause the computer system to: determine the identity of the subject reference based on a detection rules.
18. The computer system of claim 11 , further comprising computer-readable instructions that when executed by the processor cause the computer system to: determine the identity of the subject reference based on a detection rules. 20. The computer system of claim 18 , wherein the document comprises a plurality of predefined documents.