According to the paper Klaus Lüttich and Till Mossakowski. Reasoning Support for CASL with Automated Theorem Proving Systems. WADT 2006, Springer LNCS, injections have to be axiomatised with inj(x)=x. Perhaps they can even be completely omitted (depending on their use in the translation of sort generation constraints).
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According to the paper Klaus Lüttich and Till Mossakowski. Reasoning Support for CASL with Automated Theorem Proving Systems. WADT 2006, Springer LNCS, injections have to be axiomatised with inj(x)=x. Perhaps they can even be completely omitted (depending on their use in the translation of sort generation constraints).