Assertion: einsteinium's isotope | /r/HasProperty | identified in december
Facets:
value: by albert ghiorso
type: OTHER
value: by coworkers at berkeley
type: OTHER
Source sentences:
text: This isotope was identified in December 1952 by Albert Ghiorso and coworkers at Berkeley, California, in debris taken from the first thermonuclear (hydrogen bomb) explosion, “