1. Andres, J.: On the coexistence of irreducible orbits of coincidences for multivalued admissible maps on the circle via Nielsen theory Topol. Appl. 221, 596–609 (2017)
2. Bielawski, R.: The fixed point index for acyclic maps on ENR-s Bull. Pol. Acad. Sci. 35, 487–499 (1987)
3. Brown, R.F.: The Lefschetz Fixed Point Theorem Scott. Foresman and Co. Glenview III, London (1971)
4. Dzedzej, Z.: Degree of coincidence in locally convex spaces Coll. Math. Soc. Janos Bolyai 23, Topology, Budapest (1978), 377-395
5. Dzedzej, Z.: Fixed point index theory for a class of nonacyclic multivalued maps Dissert. Math. 253, 1–58 (1985)