Dieses Dokument darf im Rahmen von § 53 UrhG zum eigenen Gebrauch kostenfrei heruntergeladen, gelesen, gespeichert und ausgedruckt, aber nicht im Internet bereitgestellt oder an Außenstehende weitergegeben werden.This document may be downloaded, read, stored and printed for your own use within the limits of § 53 UrhG but it may not be distributed via the internet or passed on to external parties.Downey, RodMelnikov, AlexanderNg, Keng Meng2024-10-162024-10-162018https://oa.tib.eu/renate/handle/123456789/16897https://doi.org/10.34657/15919We prove that for every computable limit ordinal α there exists a computable linear ordering A which is Δ^(0)_(α)-categorical and α is smallest such, but nonetheless for every isomorphic computable copy B of A there exists a β<α such that A≅Δ0βB. This answers a question left open in the earlier work of Downey, Igusa, and Melnikov. We also show that such examples can be found among ordered abelian groups and real-closed fields.eng510Report