CREATE TABLE table_27877656_7 (surface VARCHAR2, score VARCHAR2, edition VARCHAR2)

For edition is 2011 europe/africa group iiib and surface where score is 6 4, 6 1 please specify all the surface
SELECT surface FROM table_27877656_7 WHERE score = "6–4, 6–1" AND edition = "2011 Europe/Africa Group IIIB"
SELECT "surface" FROM "table_27877656_7" WHERE "2011 Europe/Africa Group IIIB" = "edition" AND "6–4, 6–1" = "score"