Which is the opera by the librettist of Giuseppe Giacosa that contains the word tosca in it's name?
SELECT DISTINCT ?sbj ?sbj_label WHERE { ?sbj wdt:P31 wd:Q1344 . ?sbj wdt:P87 wd:Q372032 . ?sbj rdfs:label ?sbj_label . FILTER(CONTAINS(lcase(?sbj_label), 'tosca')) . FILTER (lang(?sbj_label) = 'en') } LIMIT 25 
opera: Q1344 giuseppe giacosa: Q372032