Last updated on June 19th, 2020
References:
- https://en.wikipedia.org/wiki/Pennsylvania
- https://www.history.com/topics/us-states/pennsylvania
- https://www.britannica.com/place/Pennsylvania-state
- http://www.theconstitutional.com/about-us/philadelphia-firsts
- https://en.wikipedia.org/wiki/Liberty_Bell
- https://en.wikipedia.org/wiki/Thomas_Edison
- https://en.wikipedia.org/wiki/The_Hershey_Company
- https://www.roadsideamerica.com/tip/35966
- https://www.nass.usda.gov/Statistics_by_State/Pennsylvania/Publications/Annual_Statistical_Bulletin/2011_2012/farm_number%20and%20land%20in.pdf
- http://beef2live.com/story-pennsylvania-ag-facts-0-105034
- https://www.history.com/this-day-in-history/children-receive-first-polio-vaccine
- https://uncoveringpa.com/pennsylvania-facts
- http://www.sheppardsoftware.com/usaweb/snapshot/Pennsylvania.htm
- https://en.wikipedia.org/wiki/Thirteen_Colonies
- https://en.wikipedia.org/wiki/Mount_Davis_(Pennsylvania)
- https://en.wikipedia.org/wiki/Vehicle_registration_plates_of_Pennsylvania
- http://edition.cnn.com/HEALTH/9807/01/braincell.transplant/
- https://www.thedrum.com/news/2017/07/13/volvo-trucks-achieves-the-guinness-world-record-largest-object-unboxed-stunt
- https://www.usmint.gov/learn/history/overview
- https://en.wikipedia.org/wiki/List_of_U.S._states_by_Amish_population
- https://en.wikipedia.org/wiki/Nuclear_reactor_accidents_in_the_United_States
- https://www.usmint.gov/learn/kids/about-us/fun-facts/page/8
- http://www.coinnews.net/2019/01/30/u-s-mint-produces-13-1-billion-coins-for-circulation-in-2018/
- http://nowiknow.com/capital-for-a-day/
- https://uncoveringpa.com/covered-bridges-in-pennsylvania
- https://www.businessinsider.in/Emoticons-were-invented-33-years-ago-today-and-theyve-basically-saved-human-communication/articleshow/49027821.cms
- https://extension.psu.edu/pennsylvania-mushroom-farmers-lead-u-s-in-mushroom-production
- http://www.uphs.upenn.edu/paharc/features/creation.html
- https://www.worldatlas.com/articles/the-oldest-hospitals-in-the-united-states.html
- https://www.history.com/topics/19th-century/andrew-carnegie
- https://www.roadsideamerica.com/tip/3591