Derived subdivisions make every PL sphere polytopal

  title={Derived subdivisions make every PL sphere polytopal},
  author={Karim A. Adiprasito and Ivan Izmestiev},
  journal={Israel Journal of Mathematics},
We give a simple proof that some iterated derived subdivision of every PL sphere is combinatorially equivalent to the boundary of a simplicial polytope, thereby resolving a problem of Billera (personal communication). 
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