[ISO 32000-1:2008] Document management – Portable document format – Part 1: PDF 1.7. ISO 32000-1:2008.

[PDF 32000-1:2008] Adobe Systems Incorporated. Document management – Portable document format – Part 1: PDF 1.7. http://www.adobe.com/devnet/pdf/pdf_reference.html.

[PDF 32000-1:2008 ExtensionLevel 3] Adobe Systems Incorporated. Adobe Supplement to the ISO 32000 (Extension Level: 3). http://www.adobe.com/devnet/pdf/pdf_reference.html.

[JCA Reference] Oracle Corporation. Java Cryptography Architecture (JCA) Reference Guide. http://docs.oracle.com/javase/7/docs/technotes/guides/security/crypto/CryptoSpec.html.