Question: when did barcelona win their first champions league
[{'answer': '1992', 'provenance': [{'wikipedia_id': '21227395', 'title': 'FC Barcelona in international football competitions', 'start_paragraph_id': 2, 'start_character': 494, 'end_paragraph_id': 2, 'end_character': 498, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '21227395', 'title': 'FC Barcelona in international football competitions', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 498, 'bleu_score': 0.950027409461844, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 2483166929143895055}, 'section': 'Section::::Abstract.'}]}]