Assertion: harpsichord's keyboard | /r/AtLocation | psaltery
Facets:
Source sentences:
text: They are thought to have originated when a keyboard was attached to a psaltery.
text: They are thought to have originated when a keyboard was attached to a psaltery.
text: They are thought to have originated when a keyboard was attached to a psaltery.
text: They are thought to have originated when a keyboard was attached to a psaltery.