In the first paragraph of the passage we are told that between the years of "1935 and 1970," the trend of critics of ancient Greek poems like the Iliad and the Odyssey was turning away from "the actual works" of the poets, to more "peripheral issues," (1-15).
We are also told that Milman Parry's son is "among those scholars responsible for a renewed interest in Homer's poetry as literary art," (48-50). So, since until 1970 we know that critics were not looking at scholarship on Homer as literary art, and that there has been a "Renewed interest in Homer's poetry as literary art," we can infer that SINCE 1970, scholarship on Homer has dealt exclusively with the Homeric poems as literary art.
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