Growing old under one child policy: current challenges and the growing need for reform

In the paper, notice how the writer integrates the first two sources into the second paragraph?, how do these two sources relate to each other?, how could the student have made it clearer?

2. The writer cited Zhang & Goza (2016) in various parts of the paper. What did these authors add to the literature on elder care in China, according to this paper?, you might focus on paragraph 2,3, and 5.