Who trained the representative whose presentation of credentials happened on February 24, 1950?
CREATE TABLE "see_also" (
  "representative" text,
  "state" text,
  "training" text,
  "title" text,
  "appointment" text,
  "presentation_of_credentials" text,
  "termination_of_mission" text,
  "reason" text
);
SELECT "training" FROM "see_also" WHERE "presentation_of_credentials"='February 24, 1950';