It was used by von Neumann, by Pontryagin in 1934 and Weil in 1940 to set up an abstract theory of commutative harmonic analysis .
Ito ay ginagamit ng von Neumann, sa pamamagitan ng Pontryagin sa 1934 at Weil sa 1940 upang i-set up ang isang mahirap unawain teorya ng commutative maharmonya analysis.