CREATE TABLE table_17379 ("Index  ( Year ) " TEXT, "Author / Editor / Source" TEXT, "Year of publication" TEXT, "Countries sampled" FLOAT, "World Ranking  ( 1 ) " TEXT, "Ranking L.A.  ( 2 ) " TEXT)

what's the author / editor / source with world ranking (1) being 73rd
SELECT "Author / Editor / Source" FROM table_17379 WHERE "World Ranking (1)" = '73rd'
SELECT "Author / Editor / Source" FROM "table_17379" WHERE "World Ranking (1)" = '73rd'