Question: when did sir alex ferguson join man utd
[{'answer': '1986', 'provenance': [{'wikipedia_id': '43223', 'title': 'Alex Ferguson', 'start_paragraph_id': 1, 'start_character': 139, 'end_paragraph_id': 1, 'end_character': 143, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '43223', 'title': 'Alex Ferguson', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 214, 'bleu_score': 0.671051626675735, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8516319076613130237}, 'section': 'Section::::Abstract.'}]}]