  We study quaternionic Bott-Chern cohomology on compact hypercomplex manifolds
and adapt some results from complex geometry to the quaternionic setting. For
instance, we prove a criterion for the existence of HKT metrics on compact
hypercomplex manifolds of real dimension 8 analogous to the one given by
Teleman [35] and Angella-Dloussky-Tomassini [3] for compact complex surfaces.
