Pier Luigi San Donnino (born Pietro Luigi Battista Sandonnini; 21 June 1846 – 17 September 1915) was an Italian lawyer and politician. He served as a member of the Senate of the Kingdom of Italy from 19 December 1913 until his death in 1915. He was also mayor of Modena, president of the Province of Modena and chairman of the Provincial Council.
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