CREATE TABLE table_name_25 (semi_finalists VARCHAR, runner_up VARCHAR, week_of VARCHAR)
When the runner-up is listed as Gigi Fernández Natalia Zvereva and the week is 26 June 2 weeks, who are the semi finalists?
SELECT semi_finalists FROM table_name_25 WHERE runner_up = "gigi fernández natalia zvereva" AND week_of = "26 june 2 weeks"