Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Name | Circuit | Date | Winning driver | Winning constructor | Report |
| --- | --- | --- | --- | --- | --- |
| Tripoli Grand Prix | Tripoli | 6 March | Emilio Materassi | Bugatti | Report |
| Opening Grand Prix | Montlhéry | 13 March | Robert Benoist | Delage | Report |
| Pozzo Circuit | Pozzo | 20 March | Gaspare Bona | Bugatti | Report |
| Provence Grand Prix | Miramas | 27 March | Louis Chiron | Bugatti | Report |
| Targa Florio | Madonie | 24 April | Emilio Materassi | Bugatti | Report |
| Messina Cup | Messina | 8 May | Antonio Caliri | Bugatti | Report |
| Alessandria Circuit | Alessandria | 8 May | Gaspare Bona | Bugatti | Report |
| Savio Circuit | Ravenna | 15 May | Gaspare Bona | Bugatti | Report |
| Burgundy Grand Prix | Dijon | 27 May | Raymond Leroy | Bugatti | Report |
| Perugia Cup | Perugia | 29 May | Emilio Materassi | Itala | Report |
| Rome Grand Prix | Parioli | 12 June | Tazio Nuvolari | Bugatti | Report |
| Picardy Grand Prix | Péronne | 12 June | Philippe Auber | Bugatti | Report |
| Thuin Circuit | Thuin | 12 June | Joseph Reynartz | Bugatti | Report |
| Eifelrennen | Nürburgring | 19 June | Rudolf Caracciola | Mercedes-Benz | Report |
| Bologna Prize | Bologna | 19 June | Emilio Materassi | Bugatti | Report |
| ACF Free For All Race | Montlhéry | 2 July | Albert Divo | Talbot | Report |
| Sporting Commission Cup | Montlhéry | 2 July | André Boillot | Peugeot | Report |
| Grand Prix de la Marne | Reims-Gueux | 10 July | Philippe Étancelin | Bugatti | Report |
| San Sebastián Grand Prix | Lasarte | 25 July | Emilio Materassi | Bugatti | Report |
| Coppa Acerbo | Pescara | 6 August | Giuseppe Campari | Alfa Romeo | Report |
| Grand Prix du Comminges | Saint-Gaudens | 7 August | François Eysermann | Bugatti | Report |
| Coppa Montenero | Montenero | 14 August | Emilio Materassi | Bugatti | Report |
| La Baule Grand Prix | La Baule | 25 August | George Eyston | Bugatti | Report |
| Milan Grand Prix | Monza | 4 September | Pietro Bordino | Fiat | Report |
| Boulogne Grand Prix | Boulogne | 10 September | Malcolm Campbell | Bugatti | Report |
| Solituderennen | Solitude | 18 September | August Momberger | Bugatti | Report |
| Thuin Circuit | Thuin | 18 September | Freddy Charlier | Bugatti | Report |
| Garda Circuit | Salò | 9 October | Tazio Nuvolari | Bugatti | Report |
| Junior Car Club 200mile race | Brooklands | 15 October | Malcolm Campbell | Bugatti | Report |
| Grand Prix du Salon | Montlhéry | 16 October | Michel Doré | La Licorne | Report |
| Apuano Circuit | Carrara | 28 October | "Niccoli" | Bugatti | Report |
Question:
When did Gaspare Bona win the Pozzo Circuit?
Answer:
20 March