Covert structural junctures involve potential and nonpotential pauses. [...] A form such 'blackbird' /blǽk-bə̀rd/ has a phonemic open juncture between the morphemes, and two structural junctures. The overt structural juncture (quite apart from the phonemic /-/) consists of the cluster /kb/, which never occurs within a single morpheme, and the covert structural juncture consists in the fact that an intonational pause never comes between the morphemes when they occur in this structural relationship.
- Nida (1949), Pag. 86