https://www.thebalancemoney.com/capital-investment-2948114

https://www.tutor2u.net/business/reference/introduction-to-investment-appraisal-revision-presentation

https://textbook.stpauls.br/Accounts_and_Finance_student/page_31.htm

https://textbook.stpauls.br/Accounts_and_Finance_student/page_30.htm

https://textbook.stpauls.br/Accounts_and_Finance_student/page_31.htm

https://learninglink.oup.com/static/5b60278d230363000febebd9/page_19.htm