The protest comes after the university closed the artist's show several months early.
Christie's spring sales in Hong Kong totaled $113.4m and scored a B+ on the HENI Auction Index, a third straight improvement.
Zhang's work takes the form of a visual letter to her daughter
The show is inspired by an 18th century painting imagining the Bank of England as a Roman ruin.
The auction house is on a roll in the city as its spring sales total $89.9m and it scores a B‑ on the HENI Auction Index, a third consecutive improvement.
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