https://www.msn.com/en-ie/money/other/how-i-manage-my-money-finance-director-retired-at-47-using-fire-method/ss-AA1KsmDG?cvid=695010bc30954b46b2b6d87bae60a8a0&ei=63#image=7

https://www.investopedia.com/terms/f/financial-independence-retire-early-fire.asp

https://www.businessinsider.com/personal-finance/investing/financial-independence-retire-early?op=1