John L. Hennessy and David A. Patterson, Computer Architecture, A Quantitative Approach, 5th Ed., Morgan Kaufmann, 2012. Chapter 1, sections 1.4 and 1.5 (pp. 17-26); Chapter 2, section 2. (pp. 87-91) The 5th Edition is available electronically via the UCSD library at http://roger.ucsd.edu/record=b7202878~S9 (UCSD Active Directory login required).
Designing fast linear algebra kernels in the presence of memory hierarchies, by Jim Demmel, UC Berkeley. Skip the last section: Fast serial matrix multiplication algorithms
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).