@article{pereira2013urbancentrality,
  title = {Urban {{Centrality}}: {{A Simple Index}}},
  shorttitle = {Urban {{Centrality}}},
  author = {Pereira, Rafael H. M. and Nadalin, Vanessa and Monasterio, Leonardo and Albuquerque, Pedro H. M.},
  year = {2013},
  journal = {Geographical Analysis},
  volume = {45},
  number = {1},
  pages = {77--89},
  issn = {1538-4632},
  doi = {10.1111/gean.12002}
}

@book{florence1948investment,
  title={Investment, Location and Size of Plant: A Realistic Enquiry Into the Structure of British and American Industries},
  author={Florence, Philip Sargant},
  volume={8},
  year={1948},
  publisher={CUP Archive}
}

@article{midelfart2002integration,
  title = {Integration and {{Industrial Specialisation}} in the {{European Union}}},
  author = {{Midelfart-Knarvik}, Karen Helen and Overman, Henry G. and Redding, Stephen and Venables, Anthony J.},
  year = {2002},
  journal = {Revue \'economique},
  volume = {53},
  number = {3},
  eprint = {3502978},
  eprinttype = {jstor},
  pages = {469--481},
  publisher = {{Sciences Po University Press}},
  issn = {0035-2764},
  doi = {10.2307/3502978}
}