Question: where is the matrix located in the osteon
[{'answer': 'haversian canal', 'provenance': [{'wikipedia_id': '1312333', 'title': 'Osteon', 'start_paragraph_id': 3, 'start_character': 116, 'end_paragraph_id': 3, 'end_character': 131, 'bleu_score': 1.0, 'section': 'Section::::Structure.\n'}]}, {'provenance': [{'wikipedia_id': '1312333', 'title': 'Osteon', 'start_paragraph_id': 4, 'start_character': 0, 'end_paragraph_id': 4, 'end_character': 1015, 'bleu_score': 0.970407102359722, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8186771435237045753}, 'section': 'Section::::Structure.\n'}]}]