REMOVE

1. Stone -- Discolouration

WHAT

1. Plaques, plaquettes (1)
2. Public art -- England -- … (1)
3. Sculpture -- England -- S … (1)
4. Tourism and art (1)

WHERE

1. ENGLAND, UK (1)
2. Sheffield, South Yorkshir … (1)

WHO

1. FARRELL, Michael (1)

WHEN

1. 1996 (1)