Roofline: an insightful visual performance model for multicore architectures, by S. Williams, A. Waterman and D. Patterson, Comm. ACM 52(4):65-76 (April 2009).
John L. Hennessy and David A. Patterson, Computer Architecture, A Quantitative Approach, 5th Ed., Morgan Kaufmann, 2012, Chapter 2, esp. §2.1 and Appendix B, §B.1 and B.4. [Available electronically via the UCSD library at http://roger.ucsd.edu/record=b7202878~S9. UCSD Active Directory login required.
What Every Programmer Should Know About Memory, by Ulrich Drepper. Parts 1 and 2