Assertion: early keyboard | /r/HasProperty | reported with single raised key
Facets:
value: in each octave
type: TEMPORAL
Source sentences:
text: Thus, early keyboards are reported with only a single raised key in each octave (B♭), and there were organs that had both B and B♭ as “natural” keys, with C♯, D♯, F♯, and G♯ as raised keys.