With no explanation, label each line with "location-GPE", "art-writtenart", "O", "person-other", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting" or "building-airport" preceded by ":".
``
To
Chicago
and
Back
``
(
where
Bay
Ganyo
appears
again
)
,
his
travel
notes
from
his
American
trip
,
spurred
a
lasting
interest
in
Chicago
,
which
today
boasts
the
largest
concentration
of
Bulgarian
immigrants
in
the
United
States
.
``:O
To:art-writtenart
Chicago:art-writtenart
and:art-writtenart
Back:art-writtenart
``:O
(:O
where:O
Bay:person-other
Ganyo:person-other
appears:O
again:O
):O
,:O
his:O
travel:O
notes:O
from:O
his:O
American:location-GPE
trip:O
,:O
spurred:O
a:O
lasting:O
interest:O
in:O
Chicago:location-GPE
,:O
which:O
today:O
boasts:O
the:O
largest:O
concentration:O
of:O
Bulgarian:location-GPE
immigrants:O
in:O
the:O
United:location-GPE
States:location-GPE
.:O