|A published field book by Kingdon Ward|
The good news is that there is a Field Book Project initiative under the Smithsonian National Museum of Natural History to increase access to these types of documents in digital format. Recently they have teamed up with the Biodiversity Heritage Library to provide central access.
Two field books that have been digitized are of interest to Primula researchers, both by Joseph Rock.
|Field book entry by Joseph Rock|
Many other Primula entries can be found in the second of Joseph Rock's field book for collections No. 8035 - 9999 from NW Yunnan and SE Tibet in 1923. Other field books of Joseph rock exist but have not been digitized.
I certainly hope that other institutions start their own Field Book projects to bring these valuable sources of information to light.