reference request for construction of expanders I'm looking for a good exposition of the explicit constructive proof of the existence of expander graph families due to Reingold Vadhan and Wigderson.  Arora/Barak has a chapter on it, but i find it to be full of typos, more serious errors, and other annoying choices (not to knock AB -- I like it generally).  I just started reading the original RVW paper, but I was wondering if there are other good sources.
You can look at this survey by Hoory, Linial, and Wigderson [1]. Chapter 9, specifically (p. 508) is on the zigzag product.

9.The zig-zag product
  9.1.   Introduction
  9.2.   Construction of an expander family using zig-zag
  9.3.   Definition and analysis of the zig-zag product
  9.4.   Entropy analysis
  9.5.   An application to complexity theory: SL=L



[1] Hoory, Shlomo, Nathan Linial, and Avi Wigderson. Expander graphs and their applications. Bulletin of the American Mathematical Society 43.4 (2006): 439-561.