CREATE TABLE table_5595 ("Date Released" TEXT, "Institute" TEXT, "Socialist" TEXT, "Social Democratic" TEXT, "Green-Communist" TEXT, "Left Bloc" TEXT, "People's Party" TEXT, "Lead" TEXT)

Name the people's party for social democratic of 30.1%
SELECT "People's Party" FROM table_5595 WHERE "Social Democratic" = '30.1%'
SELECT "People's Party" FROM "table_5595" WHERE "Social Democratic" = '30.1%'