1. LIMIT POINTS AND LONG GAPS BETWEEN PRIMES: Table 1.
2. E. Bombieri , Le grand crible dans la théorie analytique des nombres, 2nd ed., Astérisque 18 (Paris, 1987).
3. Primes in arithmetic progressions to large moduli
4. Short character sums for composite moduli
5. H. Davenport , Multiplicative number theory, 3rd ed., Graduate Texts in Mathematics 74 (Springer, New York, 2000). Revised and with a preface by H. L. Montgomery. books.google.com/books?isbn=0387950974 .