• Easley & Kleinberg, Networks, Crowds and Markets, Ch1. Overview.

• Albert-László Barabási, Network Science, Ch 1. Introduction

• Albert-László Barabási, Network Science, Ch 2, sections 2-6,9

• (for the mathematically minded:) Newman, M. E. J. The Structure and Function of Complex Networks. SIAM Review. 45 (2003): Section IV (Random Graphs) p. 20-24 and Section VII (Models of network growth) p.30-37.
• AL Barabási, R Albert, Emergence of scaling in random networks,Science, 1999.

• Linked by Albert-László Barabási
• Six Degrees by Duncan Watts.
•  Nexus by Mark Buchanan and Connected by Nicholas Christakis and James Fowler.

• Wayne E. Baker & Robert R. Faulkner, The Social Organization of Conspiracy: Illegal Networks in the Heavy Electrical Equipment Industry, American Sociological Review, 58(6), 1993.
• Sinan Aral and Marshall Van Alstyne,Network Structure and Information Advantage, working paper (full, longer paper published as The Diversity-Bandwidth Trade-Off,American Journal of Sociology, 2011

• MEJ Newman, Modularity and community structure in networks, PNAS 103 (23), p. 8577-8582 (2006).
• Palla et al., 'Uncovering the overlapping community structure of complex networks in nature and society', Nature 435, 814-818 (9 June 2005).
• Santo Fortunato, Community detection in graphs, Physics Reports 486, 75-174 (2010)

• Easley & Kleinberg, Networks, Crowds and Markets, Ch20. The Small-World Phenomenon.
• Watts & Strogatz, Collective Dynamics of Small World Networks, Nature 393, 440-442 (4 June 1998).
• Travers & Milgram, An Experimental Study of the Small World Problem,Sociometry, Vol. 32, No. 4 (Dec., 1969).

• Kilworth & Bernard, The Reveral Small-World Experiment, Social Networks, 1 (1978/79) 159-192.
• Kilworth, McCarthy, Bernard & House. (2006). The Accuracy of Small World Chains in Social Networks. Social Networks 28(1): 85-96.
• Dodds, Muhammad, and Watts, An Experimental Study of Search in Global Social Networks", Science, 301, 827-829 (2003).
• D. J. Watts, P. S. Dodds, and M. E. J. Newman. Identity and Search in Social Networks, Science, 296, 1302-1305 (2002).
• Jon Kleinberg, The Small-World Phenomenon, An Algorithmic Perspective.
• J. Kleinberg. Small-World Phenomena and the Dynamics of Information. Advances in Neural Information Processing Systems (NIPS) 14, 2001.
• Mathias & Gopal, Small worlds: How and why, PRE 2001.
• Gastner & Newman,The spatial structure of networks, Michael T. Gastner and M. E. J. Newman, Eur. Phys. J. B 49, 247–252 (2006).

Liben-Nowell et al. Geographic Routing in Social Networks, PNAS 102(33):11623-11628, 2005.