Bernard A.Lietaer, May 2002, The Future of Payment Systems,Unisys Corporation,PA,USA.
 Aryya Gango padhyay, Managing Business with Electronic Commerce:Issues & Trends,IDEA Group Publishing.
 Vesna, Hassler.Anup K Ghosh, 1998, Security Fundamentals for E-Commerce, John Wiley and Sons Inc, New York.
 Paul S. Turner, Diane B. Wunnicke, Managing the Risks of the Payment Systems, John Wiley and Sons Inc, New York.
 Jonathan(EDT) Reuvid, Chris Ollington, July 2004,The Secure Online Business Handbook: ECommerce, IT Functionality, and Business Continuity, ISBN: 0749442212, Korgan Page.
 Ravi Kalkota, Andrew B Whinston, 1996,Frontiers of Electronic Commerce, ISBN:0201845202, Addison-Wesley Publications
 William Stallings, 1999, Cryptography and Network Security: Principles and Practice, ISBN:0138690170, Prentice Hall, Upper Saddle River, N.J, USA.
 Donal O'Mahon, Michael Peirce, Hitesh Tewari, Electronic payment systems for ECommerce,Second Edition, ISBN:1580534635, Artech House Inc, MA, USA.
 M. Peirce, Multi-Party Electronic Payments for Mobile Communication, PhD thesis in Computer Science,University of Dublin, Trinity College,Department of Computer Science, October 31st, 2000, https://www.cs.tcd.ie/publications/tech-reports/reports.01/TCD-CS-2001- 26.pdf [2006-05-20].
 Davies G, A History of Money: From Ancient Times to the Present Day , University of Wales Press, 2003.
 Stephen A Thomas, SSL and TLS essentials for Securing the Web,ISBN: 0471383546, John Wiley and Sons Inc, New York.
 P.Wayne, "Digital Cash: Commerce on the Net", Academic Press, (1996).
 Ajay C.Shantilal, Harish S.Gopalakrishnan, Mobile Payment Services, ECE 578 project, Oregon state Univeristy,Spring 2002.
 D.Buhan, YC Cheong, CL Tan, “Mobile Payments In M-Commerce”, Telecom. Media. Networks, September 2002.
 Jari Kytojoki, Vesa Karpijoki, Micropayments - Requirements and Solutions, Department of omputer Science, Helsinki University of Technology, 10th January, 2000.