At Lvov, however, Kuratowski worked with Banach and they answered some fundamental problems on measure theory . Ulam, who had become Banach 's research student also worked with them.
Sa Lvov, gayunpaman, Kuratowski nagtrabaho sa Banach at sila ay sumagot ng ilang pangunahing problema sa panukalang-batas theory. Ulam, na maging Banach 's research mag-aaral din nagtrabaho sa kanila.