Ordering large-plant bifolios in accordance with pharma section?

[Koen G]

There are also concentrations in both sections. Most notably 102r. But also in the large plants that are currently (re)bound closest to the pharma section. I'm starting to fear though that the number of actual matches is too low to determine what is actually going on. 

Would there be a possibility that both sections were originally combined? Like a few large plants, then the corresponding foldout with "pharma stuff", then some more large plants, another foldout etc?