SWIFT-community.

NACHA - The Electronic payments Assocition 

PayItGreen
-Experience the vision - video

PayItGeen - Good for the environment. Good for You.

EU commission initiative on e-invoicing

European Commission website on e-invoicing

Status report from the Expert Group on E-invoicing

Haq, S. (2007) Electronic Invoicing Gains as Adoption Barriers Fall. Financial Executive, Sep2007, vol. 23, iss. 7.

Mallat (2006) Consumer and merchant adoption of mobile payments. PhD Thesis at HSE, A-285.