Question: who wrote about the emerging white collar class in the 1950s
[{'answer': 'Milovan Đilas', 'provenance': [{'wikipedia_id': '286819', 'title': 'New class', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 13, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '286819', 'title': 'New class', 'start_paragraph_id': 6, 'start_character': 0, 'end_paragraph_id': 6, 'end_character': 1094, 'bleu_score': 0.925775684601789, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15849639776990250556}, 'section': 'Section::::Milovan Đilas\' "New Class".\n'}]}]