https://www.osti.gov/opennet/manhattan-project-history/index.htm
The Manhattan Project: An Interactive History
the manhattan projectinteractivehistory
https://www.livescience.com/manhattan-project.html
What was the Manhattan Project? | Live Science
Feb 27, 2020 - Nuclear weapons research began before the outset of World War II. But the Manhattan Project was a different beast.
the manhattan projectlive science