Werner J. Dannhauser, Nietzsche's View of Socrates, Cornell University Press, 1974.

About the book (from review of the book in Dialogue, 1978):

The problem W. Dannhauser undertakes to study in this book is obviously a very interesting one for the student of Nietzsche’s philosophy. Can one reduce the question of Nietzsche’s relation to Socrates to whether Nietzsche really attacks Socrates or simply admires him? Nietzsche often admires Socrates in order to reject him in the end; he often attacks Socrates because he accepts his philosophizing profoundly. He said himself in a fragmentary sentence, written around 1875, quoted by the author: “Socrates, simply to confess it, stands so near to me that I almost always fight a battle with him” (p. 15). Socrates and Plato moreover had already done something similar in their critique of the myths. Studying Nietzsche’s view of Socrates is, indeed, studying Nietzsche’s thought. What the author claims to do is to understand Nietzsche through Socrates (cf. pp. 13, 15).

Online:
Amazon