10 percent before the cival war
It was a six months trip across 2000 miles
Sources are used in a paper to show what ideas inspired you and whose theories you would be using and you cite the sources in order to avoid plagiarism. If you don't have sources, your paper will not be valid and you could get accused of plagiarism. The more sources you use the better but you should keep in mind that they need to be important for the paper and used with a purpose and not just to increase the number of sources.
can you explain your question more clearly?
Less developed countries, post-socialist countries, transition, social market economy
