CREATE TABLE table_1620397_2 (author VARCHAR2, featuring VARCHAR2, released VARCHAR2)

Name the author for peri and april 2010
SELECT author FROM table_1620397_2 WHERE featuring = "Peri" AND released = "April 2010"
SELECT "author" FROM "table_1620397_2" WHERE "April 2010" = "released" AND "Peri" = "featuring"