who was the chairman of beşiktaş j . k . and also 2012–13 beşiktaş j . k . season ?
SELECT DISTINCT var_uri where brack_open dbr_2012–13_Beşiktaş_J.K._season dbo_chairman var_uri sep_dot dbr_Beşiktaş_J.K sep_dot dbo_chairman var_uri brack_close