Assertion: lr's isotope | /r/HasProperty | specified as special case
Facets:
value: for 1h
type: LOCATION
value: often
type: TEMPORAL
Source sentences:
text: As a special case, the three naturally occurring isotopes of the element hydrogen are often specified as H for 1H (protium), D for 2H (deuterium), and T for 3H (tritium).