Eichel, L., and C. Zukin.2009. Philadelphia Quality of Life Survey . http://www.pewtrusts.org/uploadedFiles/www.pewtrustsorg/Reports/Civic_initiative/POLL%20REPORT%20II%20FINAL.pdf.
2.
Pressman, J., and A. Wildalvsky.1973. Implementation. Berkeley: University of California Press.