Organizations

- Keith Spencer Collection (CA County Maps & Books) - https://keithwspencer.net/Library/Library.shtml

- Mount Diablo Initial Point (By John Pettley - Zoom Presentation) - https://us02web.zoom.us/rec/play/rFFvZZFDCEHn9t17Qb2FYZgLiEs-J6_MZ_7FvYr...

- Curta Calculators:
Info/History - www.vcalc.net/cu.htm
The 3D-Printed Curta - www.youtube.com/watch?v=j9uRckJLqLk

- Historical Emporium (Period Clothing) - https://historicalemporium.com

- Time and Navigation - https://timeandnavigation.si.edu

- Museum of Measurement and Time - www.museumofmeasurementandtime.org/services.html

- Plumb Bobs (Coming Soon)