With no explanation, label each line with "O", "person-other", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
In
1969
,
Borgman
,
Kornneef
,
and
Slingerland
conducted
a
photometric
survey
of
the
cluster
and
assigned
letters
to
the
stars
they
measured
.
In:O
1969:O
,:O
Borgman:person-other
,:O
Kornneef:person-other
,:O
and:O
Slingerland:person-other
conducted:O
a:O
photometric:O
survey:O
of:O
the:O
cluster:O
and:O
assigned:O
letters:O
to:O
the:O
stars:O
they:O
measured:O
.:O