For a feature-changing map to be present in the phonology, a Phono-Constraint C must dominate "some" relevant constraint on I-O Faithfulness as well as every other phonological constraint *M that militates against the desired output M.
- McCarthy & Prince (2004), a pag.413

If the phonology contains a further context in which the unmarked elements appear, due to a constraint ranked "above" what we have called "Phono-Constraint", then something that looks quite like underapplication can result.
- McCarthy & Prince (2004), a pag.426