Columbia subject headings:
Duomo (Modena, Italy)
Modena (Italy)--Buildings, structures, etc.
Harvard subject headings:
Duomo (Modena, Italy)--Conservation and restoration.
Modena (Italy)--Buildings, structures, etc.--Conservation and restoration.
Torre Ghirlandina (Modena, Italy)--Conservation and restoration.
Princeton subject headings:
Duomo (Modena, Italy)
Modena (Italy)--Buildings, structures, etc.