Recently, L. Buhovsky, A. Logunov and S. Tanny proved the (strong) Poisson
bracket conjecture by Leonid Polterovich in dimension 2. In this note, instead
of open cover constituted of displaceable sets in their work, considering open
cover constituted of topological discs we give a sufficient and necessary
condition that Poisson bracket invariants of these covers are positive.Comment: 10 page