# Notebook 61 [Erwin Raisz notebooks]

> Notebook labeled Book 4

**Wikidata**: [Q62564715](https://www.wikidata.org/wiki/Q62564715)  
**Source**: https://4ort.xyz/entity/notebook-61-erwin-raisz-notebooks-


## References

1. finding aid
2. [Source](http://id.lib.harvard.edu/alma/990148216920203941/catalog)