Question: who are the authors of the famous book titled natural capitalism
[{'answer': 'Paul Hawken', 'provenance': [{'wikipedia_id': '45291', 'title': 'Natural Capitalism', 'start_paragraph_id': 1, 'start_character': 90, 'end_paragraph_id': 1, 'end_character': 101, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Amory Lovins', 'provenance': [{'wikipedia_id': '45291', 'title': 'Natural Capitalism', 'start_paragraph_id': 1, 'start_character': 103, 'end_paragraph_id': 1, 'end_character': 115, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Hunter Lovins', 'provenance': [{'wikipedia_id': '45291', 'title': 'Natural Capitalism', 'start_paragraph_id': 1, 'start_character': 120, 'end_paragraph_id': 1, 'end_character': 133, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '45291', 'title': 'Natural Capitalism', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 237, 'bleu_score': 0.8815741981066071, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4698459201667605186}, 'section': 'Section::::Abstract.'}]}]