Columbia subject headings:
City walls--Design and construction--Early works to 1800.
Martini, Francesco di Giorgio, 1439-1502.
Mechanical engineering--Early works to 1800.
Mechanical engineers--Italy--Biography.
Harvard subject headings:
City walls--Design and construction--Early works to 1800.
Martini, Francesco di Giorgio, 1439-1502
Mechanical engineering--Early works to 1800
Mechanical engineers--Italy--Biography.
Princeton subject headings:
City walls--Design and construction--Early works to 1800.
Martini, Francesco di Giorgio, 1439-1502.
Mechanical engineering--Early works to 1800.
Mechanical engineers--Italy--Biography.