CREATE TABLE table_41518 ("Date" TEXT, "Cover model" TEXT, "Centerfold model" TEXT, "Interview subject" TEXT, "20 Questions" TEXT)

Who was the Centerfold Model when the Cover Model was Julie Lynn Cialini?
SELECT "Centerfold model" FROM table_41518 WHERE "Cover model" = 'julie lynn cialini'
SELECT "Centerfold model" FROM "table_41518" WHERE "Cover model" = 'julie lynn cialini'