CREATE TABLE table_35956 ("Date" CLOB, "Tournament" CLOB, "Surface" CLOB, "Opponent" CLOB, "Score" CLOB)

What is the surface of the tournament with Sascha Kloer as the opponent?
SELECT "Surface" FROM table_35956 WHERE "Opponent" = 'sascha kloer'
SELECT "Surface" FROM "table_35956" WHERE "Opponent" = 'sascha kloer'