Table:
text: 2009 Sidecarcross World Championship
Calendar
Calendar
Date_ Place Race_winners GP_winner Source_
23 August Kiviõli Janis Daiders / Lauris Daiders Janis Daiders / Lauris Daiders Result
6 September Saint-Jean Jan Hendrickx / Tim Smeuninx Janis Daiders / Lauris Daiders Result
6 September Saint-Jean Daniël Willemsen / Sven Verbrugge Janis Daiders / Lauris Daiders Result
13 September Rudersberg Joris Hendrickx / Kaspars Liepins Joris Hendrickx / Kaspars Liepins Result
13 September Rudersberg Stuart Brown / Luke Peters Joris Hendrickx / Kaspars Liepins Result
27 September Jauer Belgium Belgium Belgium

Question: From the 2009 World Sidecarcross Championship calendar listing, what is the source for September 6th?