In which cities were the 1976 winter and summer games held?
cities refer to city_name; 1976 winter and summer games refer to games_name IN ('1976 Winter', '1976 Summer');
SELECT T2.city_name FROM games_city AS T1 INNER JOIN city AS T2 ON T1.city_id = T2.id INNER JOIN games AS T3 ON T1.games_id = T3.id WHERE T3.games_name IN ('1976 Summer', '1976 Winter')