Columbia subject headings:
Harvard subject headings:
Biographies
Choi, Hong Hi
Gillis, Alex
Kim, Un-yong, 1931-2017
Tae kwon do--History.
Princeton subject headings:
Choi, Hong Hi.
Gillis, Alex.
Kim, Un-yong, 1931-
Martial artists--Biography.
Tae kwon do--History.