The current paper addresses non-local results on approximate and fixed points theorems for set-valued mappings in the context of symmetric $ (q_1, q_2) $-quasi-metric spaces, considering the regularity of the mappings involved. From these results, we derive non-local coincidence and double fixed point theorems for a pair of set-valued mappings, as well as non-local (Hölder) approximate, Milyutin, and Lyusternik-Graves theorems, along with (Hölder) approximate and implicit multifunction theorems in the same context. Our results extend those recently presented in the literature [1,25,23,2,26], which encompass classical results such as Nadler's multi-valued fixed point theorem [22] and Dontchev-Rockafellar's fixed point theorem [11].
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