You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Textual_criticism

Context:
Whereas Greg had limited his illustrative examples to English Renaissance drama, where his expertise lay, Bowers argued that the rationale was "the most workable editorial principle yet contrived to produce a critical text that is authoritative in the maximum of its details whether the author be Shakespeare, Dryden, Fielding, Nathaniel Hawthorne, or Stephen Crane. The principle is sound without regard for the literary period." For works where an author's manuscript survived – a case Greg had not considered – Bowers concluded that the manuscript should generally serve as copy-text. Citing the example of Nathaniel Hawthorne, he noted:

Question:
What is the main criticism of Greg's work?

works where an author's manuscript survived