Question: when was the last time the vikings were in the superbowl
[{'answer': 'January 9 , 1977', 'provenance': [{'wikipedia_id': '20134', 'title': 'Minnesota Vikings', 'start_paragraph_id': 19, 'start_character': 165, 'end_paragraph_id': 19, 'end_character': 181, 'bleu_score': 1.0, 'section': 'Section::::History.:1970s.\n'}]}, {'provenance': [{'wikipedia_id': '20134', 'title': 'Minnesota Vikings', 'start_paragraph_id': 19, 'start_character': 0, 'end_paragraph_id': 19, 'end_character': 208, 'bleu_score': 0.8932326983013691, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4879206639224876873}, 'section': 'Section::::History.:1970s.\n'}]}]