“…Additional references on hypermultiplet moduli spaces and instantons are [11,12,13,14,15,16,17]. Furthermore a program towards formulating an instanton calculus based on N = 2 supersymmetric actions with Euclidean signature was started in [18,19]. 2 Membrane instantons were also considered in [20,21], but our analysis below differs since we do not assume the existence of a rotational symmetry between the RR scalars in the UHM scalar metric.…”