Hyperk\"ahler Nahm transform

Given two hyperk"ahler manifolds $M$ and $N$ and a quaternionic instanton on their product, a hyperk"ahler Nahm transform can be defined, which maps quaternionic instantons on $M$ to quaternionic instantons on $N$. This construction includes the case of Nahm transform for periodic instantons on ${\text{bR}}^4$, the Fourier-Mukai transform for instantons on K3 surfaces, as well as the Nahm transform for ALE instantons.