Working Paper Tasks

- [x] Finish adding all Bibliography references
- [x] Rename the `References` as `Bibliography`
- [x] Reword conclusion section to reflect new results
- [ ] Flesh out literature review *if time*
  - [ ] More recent work on input-output models
  - [ ] More recent work on Spatial Interaction
  - [ ] AI?
- [x] How best to cite `estios`
  - [x] Add Alan as an author
  - [x] Register a DOI