question: What is the Copa Libertadores 1999 result for team vasco, which made the group stage in the Copa Mercosur 1999?
answer: SELECT copa_libertadores_1999 FROM table_name_62 WHERE copa_mercosur_1999 = "group stage" AND team = "vasco"
context: CREATE TABLE table_name_62 (copa_libertadores_1999 VARCHAR, copa_mercosur_1999 VARCHAR, team VARCHAR)