CREATE TABLE table_67374 ("Year" TEXT, "Men's singles" TEXT, "Men's doubles" TEXT, "Women's doubles" TEXT, "Mixed doubles" TEXT)

What were the names of the mixed doubles pair for the year that Ralph Nichols played in the men's singles match?
SELECT "Mixed doubles" FROM table_67374 WHERE "Men's singles" = 'ralph nichols'
SELECT "Mixed doubles" FROM "table_67374" WHERE "Men's singles" = 'ralph nichols'