1. Pfitzmann, A.: Anonymity, Unlinkability, Unobservability, Pseudonymity and Identity Management - A Consolidated Proposal for Terminology (2005)
2. http://slis.cua.edu/ihy/fall01/tpedoc/pl106229.pdf
3. http://www.ntia.doc.gov/ntiahome/ntiageneral/esign/105b/esign7.htm
4. Blythe, S.E.: Digital Signature Law of the United Nations, European Union, United Kingdom and United Stats: Promotion of Growth in E-Commerce with Enhanced Security, 11 RICH. J.L. & TECH. 2 (2005), at: http://law.richmond.edu/jolt/v11i2/article6.pdf
5. http://europa.eu.int/eur-lex/pri/en/oj/dat/2000/l_013/l_01320000119en00120020.pdf