1. American Gas Association, Cryptographic Protection of SCADA Communications; Part 1: Background, Policies and Test Plan, AGA Report No. 12 (Part 1), Draft 5 (www.gtiservices.org/security /AGA12Draft5r3.pdf), April 14, 2005.
2. American Gas Association, Cryptographic Protection of SCADA Communications; Part 2: Retrofit Link Encryption for Asynchronous Serial Communications, AGA Report No. 12 (Part 2), Draft (www.gtiservices.org/security/aga-12p2-draft-0512.pdf), May 12, 2005.
3. American National Standards Institute/Instrumentation Systems and Automation Society, Security Technologies for Manufacturing and Control Systems (ANSI/ISA-TR99.00.01-2004), October 2004.
4. American National Standards Institute/Instrumentation Systems and Automation Society, Integrating Electronic Security into the Manufacturing and Control Systems Environment (ANSI/ISA-TR99.00.02-2004), October 2004.
5. American Petroleum Institute, API 1164, SCADA Security, American Petroleum Institute, September 1, 2004.