The point of this question is to help me find references regarding squashed spheres in general dimension. I am interested in the general theory of squashing for arbitrary dimension. All of the references or applications to squashing that I've seen thus far refer to specific dimensions, such as 3 or 7, which are rather exceptional from a Mathematical point of view. I am not sure if the formalism developed in these dimensions can be straightforwardly applied to any dimension, or if the situation is more complicated.
This is purely a mathematical subject, but it has applications in gravity and string theory.
Note: for those who don't know, squashing is a technical term, and not a heuristic one. Squashing is a special type of deformation that preserves topology and the coset structure of the manifold. For example in 3 dimensions the sphere has SO(4) isometry group, but squashing reduces it to SU(2).