Bott is often quoted as saying "Evrey mathematician has a secret weapon. Mine is Morse theory." Every time I see his name I've tried to look up a source. Finally found one:https://mathoverflow.net/questions/100316/raoul-botts-quote-...
Anyway if you enjoyed this you might also enjoy
https://www.numdam.org/item/10.1007/BF02698544.pdf
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