Assertion: concertina | /r/CapableOf | satisfy the regularity
Facets:
value: in the hayden system
type: LOCATION
value: fully
type: DEGREE
Source sentences:
text: It seems unlikely that a Hayden Duet larger than 67 buttons could ever be practical, so there is no hope of actually making a concertina which fully satisfies the regularity possible in the Hayden System.