1. Belkin P (2008) The European Union’s energy security challenges. CRS Report for Congress. Library of Congress, New York
2. Brög W et al (2005) Societal megatrends. Like it or not, the framework is set. Transportation is also embedded in this changing world and efforts have been allocated to envisage its development, 56th UITP World Congress.
3. Central Statistics Office (2013) Energy statistics 2013. Central Statistics Office, National Statistical Organisation and the Ministry of Statistics and Programme Implementation, Government of India
4. Chan CK, Yao X (2008) Air pollution in mega cities in China. Atmos Environ 42:1–42
5. Delle Site P, Salucci, MV, Hoppe M, Seppänen TM, Christ A, Arsenio E, van Grinsven A, Morris D, Anoyrkati E, Brooks R, Hepting M, Kompil M, Tavlaki E, Micharikopoulos D, Akkermans L (2012) List of potential megatrends influencing transport system and mobility behaviour. In: OPTIMISM. Optimising passenger transport information to materialize insights for sustainable mobility. Brüssel: European Commission