CREATE TABLE table_31470 ("Event" FLOAT, "Circuit" CLOB, "GT3 Pro Cup Winner" CLOB, "GT3 Pro / Am Cup Winner" CLOB, "GT3 Citation Cup Winner" CLOB, "GT4 Cup Winner" CLOB)

List all GT4 Cup winners played on the Spa-Francorchamps Report.
SELECT "GT4 Cup Winner" FROM table_31470 WHERE "Circuit" = 'Spa-Francorchamps Report'
SELECT "GT4 Cup Winner" FROM "table_31470" WHERE "Circuit" = 'Spa-Francorchamps Report'