Letters would be an example of a primary source
In the illustrative case of Rome, Italy, in the 1920s and 1930s, suburbs were intentionally created ex novo in order to give lower classes a destination, in consideration of the actual and foreseen massive arrival of poor people from other areas of the country.
so railways
It provided the minimal assistance initially but eventually increased assistance and market regulation because they wanted to show minimum capability to what they were doing and how they were doing it.
3. Industries became more mechanized
