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YesBy defining ab=0 (zero product) every Banach space become a Banach algebra.
A Banach space is a normed vector space which is complete, in the sense that Cauchy sequences have limits.
Michio Nagumo has written:
'Introduction to the theory of Banach space' -- subject(s): Banach spaces
A. A. Tolstonogov has written:
'Differential inclusions in a banach space' -- subject(s): Banach spaces, Differential inclusions
Stefan Banach is the inventor of Banach algebra.