CREATE TABLE table_15023 ("Year" FLOAT, "Men's singles" TEXT, "Women's singles" TEXT, "Men's doubles" TEXT, "Women's doubles" TEXT, "Mixed doubles" TEXT)

Name the women's singles for 1991
SELECT "Women's singles" FROM table_15023 WHERE "Year" = '1991'
SELECT "Women's singles" FROM "table_15023" WHERE "Year" = '1991'