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:
| Outcome | Date | Tournament | Surface | Partner | Opponents | Score |
| --- | --- | --- | --- | --- | --- | --- |
| Winner | 15 June 1997 | Gerry Weber Open | Grass | Michael Stich | David Adams Marius Barnard | 7–6, 6–3 |
| Winner | 15 July 2001 | Catella Swedish Open | Clay | Jens Knippschild | Simon Aspelin Andrew Kratzmann | 7–6 (7–3) , 4–6, 7–6 (7–5) |
| Winner | 30 September 2001 | Salem Open | Hardcourt | André Sá | Petr Luxa Radek Štepánek | 6–0, 7–5 |
| Winner | 3 February 2002 | Milan Indoor | Carpet | Andrei Olhovskiy | Julien Boutter Max Mirnyi | 3–6, 7–6 (7–5) , [12–10] |
| Winner | 14 April 2002 | Estoril Open | Clay | Andrei Olhovskiy | Simon Aspelin Andrew Kratzmann | 6–3, 6–3 |
| Winner | 14 September 2003 | BCR Open Romania | Clay | Sargis Sargsian | Simon Aspelin Jeff Coetzee | 7–6 (9–7) , 6–2 |
| Runner-up | 13 April 1997 | Salem Open | Hardcourt | Jeff Tarango | Martin Damm Daniel Vacek | 3–6, 4–6 |
| Runner-up | 4 May 1997 | BMW Open | Clay | Jens Knippschild | Pablo Albano Àlex Corretja | 6–3, 5–7, 2–6 |
| Runner-up | 5 October 1997 | Basel | Carpet (i) | Jim Grabb | Tim Henman Marc Rosset | 6–7, 7–6, 6–7 |
Question:
Which Date has a Tournament of bmw open?
Answer:
4 May 1997