The answer you may be looking for is FLAT.
Answer:
yes, it could be used.
Explanation:
Engels work, relating to unfavorable working conditions, relates directly to the time and place of the diary´s entry, and for that reason, it could be used as a firsthand personal illustration of Engel´s thesis. Nevertheless, it should be treated as merely one example, one single viewpoint, upon a problem whose context and dimensions are far greater than one man´s perspective; that is to say, the entry diary can work as one historical source amongst the many more that a reliable argument should employ in trying to support and fundament Engel´s thesis.
