Assertion: double bass's string | /r/HasProperty | two strings per course
Facets:
Source sentences:
text: Other mandolin varieties differ primarily in the number of strings and include four-string models (tuned in fifths) such as the Brescian and Cremonese, six-string types (tuned in fourths) such as the Milanese, Lombard and the Sicilian and 6 course instruments of 12 strings (two strings per course) such as the Genoese.
text: There has also been a twelve-string (three strings per course) type and an instrument with sixteen-strings (four strings per course).