50 years ago, General Dynamics' YF-16 beat Northrop's YF-17 to be the USAF's next tactical fighter. This video explores development of light fighters in the US during the middle 1960s and early 1970s and introduces the five competitors to the YF-16.
Sources
"American Secret Projects: Fighters" by Tony Buttler is indispensible for anyone interested in the development of US aircraft during the Cold War
Although there are many good books on the F-16 and F/A-18, the best source about their early development is the peerless Secret Projects Forum. For example:
Northrop N530 and N600: https://www.secretprojects.co.uk/threads/northrop-p-530-p-600-p-610-yf-17-design-evolution.448/
Boeing: https://www.secretprojects.co.uk/threads/boeing-lightweight-fighter-design-to-lwf-requirement.11033/
General Dynamics: https://www.secretprojects.co.uk/threads/adf-to-lwf-evolution-of-the-general-dynamics-f-16.1335/