Question: who wrote edge of a broken heart by vixen
[{'answer': 'Richard Marx', 'provenance': [{'wikipedia_id': '12387504', 'title': 'Vixen (Vixen album)', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 12, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Fee Waybill'}]