use Gephi to plot the full +500mb cross citation with nodes with department info

We can try to use [Gephi](https://gephi.org/) to plot the full map.

The only thing here that we would need to add would be the physics department (paper). Instead of getting this from the api by calling each id we can easily get this info as the doi ID concatenates the department (paper) by doing something like:

'10.1103/**PhysRevD**.49.748'

```python
doi_num = '10.1103/PhysRevD.49.748'
s = doi_num
journal_id = s[s.find('/')+1:s[:s.rfind(".")].rfind(".")]
```