Assertion: paper's material | /r/CapableOf | become available
Facets:
value: in the early 20th century
type: TEMPORAL
Source sentences:
text: Applying this idea to corrugated boxboard was a straightforward development when the material became available in the early 20th century.
text: Applying this idea to corrugated boxboard was a straightforward development when the material became available around the turn of the twentieth century.