Assertion: wave's period | /r/HasProperty | 14 sec periods
Facets:
value: days later
type: TEMPORAL
Source sentences:
text: For example, the first waves of a new swell might have a period of 20-25 seconds (secs), followed by 17 sec swells 2 days later, then 14 sec periods and 13 sec periods even days later, and so on.