https://www.britannica.com/topic/Great-Railroad-Strike-of-1877

https://www.digitalhistory.uh.edu/disp_textbook.cfm?smtID=2&psid=3189

https://www.history.com/news/1877-railroad-strike-trains

https://nationalponyexpress.org/historic-pony-express-trail/1860-1861-history/

https://www.britannica.com/topic/Pony-Express

https://www.history.com/news/10-things-you-may-not-know-about-the-pony-express

https://guides.loc.gov/world-of-1898/rough-riders

https://www.britannica.com/topic/Rough-Rider-United-States-cavalry

https://www.history.com/news/buffalo-soldiers-spanish-american-war-san-juan-hill-rough-riders

https://history.state.gov/milestones/1961-1968/cuban-missile-crisis

https://www.history.com/this-day-in-history/october-22/cuban-missile-crisis

https://www.jfklibrary.org/learn/about-jfk/jfk-in-history/cuban-missile-crisis

https://www.jfklibrary.org/learn/about-jfk/jfk-in-history/the-bay-of-pigs

https://www.history.com/this-day-in-history/april-17/the-bay-of-pigs-invasion-begins

https://www.britannica.com/event/Bay-of-Pigs-invasion

https://www.britannica.com/event/United-States-presidential-election-of-1960

https://www.jfklibrary.org/asset-viewer/1960-presidential-election-returns

https://www.loc.gov/classroom-materials/united-states-history-primary-source-timeline/post-war-united-states-1945-1968/presidential-election-1960/

https://www.presidency.ucsb.edu/statistics/elections/1960

https://www.pbs.org/opb/thesixties/topics/culture/index.html

https://www.britannica.com/topic/1960s-counterculture

https://www.history.com/topics/1960s

https://www.publichealth.va.gov/exposures/agentorange/

https://www.science.org/content/article/vietnam-health-effects-agent-orange-remain-uncertain-50-years-later

https://www.ncbi.nlm.nih.gov/books/NBK236351/

https://www.afhistory.af.mil/FAQs/Fact-Sheets/Article/458992/1965-operation-rolling-thunder/

https://www.history.com/articles/operation-rolling-thunder

https://www.nationalmuseum.af.mil/Visit/Museum-Exhibits/Fact-Sheets/Display/Article/195909/north-vietnam-rolling-thunder/