<Tr> <Td> Nadia Petrova </Td> <Td> 1999--17 </Td> <Td> 13 </Td> <Td> 24 </Td> <Td> 0 </Td> <Td> 37 </Td> <Td> </Td> </Tr> <Tr> <Td> Samantha Stosur </Td> <Td> 1999--</Td> <Td> 9 </Td> <Td> 24 </Td> <Td> </Td> <Td> 36 </Td> <Td> </Td> </Tr> <Tr> <Td> Tracy Austin </Td> <Td> 1978--94 </Td> <Td> 30 </Td> <Td> </Td> <Td> </Td> <Td> 35 </Td> <Td> </Td> </Tr> <Tr> <Td> Roberta Vinci </Td> <Td> 1999--</Td> <Td> 10 </Td> <Td> 25 </Td> <Td> 0 </Td> <Td> 35 </Td> <Td> </Td> </Tr>

Who has won the most tennis singles titles