Marc-Antoine Parseval
Marc-Antoine Parseval des Chênes ( 27 April 1755 – 16 August 1836 ) was a French mathematician , most famous for what is now known as Parseval's theorem , which presaged the unitarity of the Fourier transform . 
<triplet> Marc-Antoine Parseval <subj> 27 April 1755 <obj> date of birth <subj> 16 August 1836 <obj> date of death