CREATE TABLE "2013" (
  "date" text,
  "place" text,
  "race_winners" text,
  "gp_winner" text,
  "source" text
);

Question: What source has a race winner of ben adriaenssen / ben van den bogaart, and the gp winner of ben adriaenssen / ben van den bogaart, for the date of 1 april?
SQL: SELECT "source" FROM "2013" WHERE "race_winners"='ben adriaenssen / ben van den bogaart' AND "gp_winner"='ben adriaenssen / ben van den bogaart' AND "date"='1 april';

Question: What is the GP winner for the Race winners valentin giraud / nicolas musset, and a place genk?
SQL: SELECT "gp_winner" FROM "2013" WHERE "race_winners"='valentin giraud / nicolas musset' AND "place"='genk';

Question: What is the date for a source of result and a place of iffendic?
SQL: SELECT "date" FROM "2013" WHERE "source"='result' AND "place"='iffendic';

Question: What date has a place of chernivtsi, and a race winners of etienne bax / kaspars stupelis? What
SQL: SELECT "date" FROM "2013" WHERE "place"='chernivtsi' AND "race_winners"='etienne bax / kaspars stupelis';

Question: What is the GP winner with a place of genk, with race winners ben adriaenssen / ben van den bogaart?
SQL: SELECT "gp_winner" FROM "2013" WHERE "place"='genk' AND "race_winners"='ben adriaenssen / ben van den bogaart';

Question: What is the race winners for the date of 23 june?
SQL: SELECT "race_winners" FROM "2013" WHERE "date"='23 june';