2026-06-08T09:33:39Zhttps://docta.ucm.es/rest/oai/request

oai:docta.ucm.es:20.500.14352/577132023-08-26T07:39:14Zcom_20.500.14352_14col_20.500.14352_15

Rodríguez Sanjurjo, José Manuel 2023-06-20T17:03:55Z 2023-06-20T17:03:55Z 1989-01 0002-9939 10.2307/2046760 https://hdl.handle.net/20.500.14352/57713 http://www.ams.org/journals/proc/1989-105-01/S0002-9939-1989-0931746-X/S0002-9939-1989-0931746-X.pdf http://www.ams.org/ In this interesting paper, the author gives a stability condition for the fixed point property in terms of K. Borsuk's fundamental metric on a hyperspace of a compact metric space. This condition is equivalent to that originally given by V. L. Klee [Colloq. Math. 8 (1961), 43–46] but it reflects richer properties. By replacing exact conditions with their proximate analogues, the author introduces a notion of proximately universal maps and studies many of their properties. In particular, he investigates their preservation under composition with weakly refinable and refinable maps to get improvements of results of E. E. Grace [Proc. Amer. Math. Soc. 98 (1986), no. 2, 329–335] and C. W. Ho [Fund. Math. 111 (1981), no. 2, 169–177]. eng restricted access Stability of the fixed-point property and universal maps journal article