For the Crew with Year 9 2nd Quads of STM, Year 9 1st Quads of SOM, and a Year 8 3rd Quads of STA what was the Year 8 1st Quads?
CREATE TABLE "winning_head_of_the_river_championship_e" (
  "crew" real,
  "year_10_1st_quad" text,
  "year_10_2nd_quad" text,
  "year_10_3rd_quad" text,
  "year_10_4th_quad" text,
  "year_10_single_scull" text,
  "year_9_1st_quad" text,
  "year_9_2nd_quad" text,
  "year_9_3rd_quad" text,
  "year_9_4th_quad" text,
  "year_9_single_scull" text,
  "year_8_1st_quad" text,
  "year_8_2nd_quad" text,
  "year_8_3rd_quad" text,
  "year_8_4th_quad" text,
  "year_8_single_scull" text
);
SELECT "year_8_1st_quad" FROM "winning_head_of_the_river_championship_e" WHERE "year_9_2nd_quad"='stm' AND "year_9_1st_quad"='som' AND "year_8_3rd_quad"='sta';