Jacques Bertin: Semiology of Graphic
http://innovis.cpsc.ucalgary.ca/innovis/uploads/Courses/InformationVisualizationDetails/09Bertin.pdf
Stephen Few: "Telling Compelling Stories with Numbers"
http://nces.ed.gov/programs/slds/pdf/08_F_06.pdf
Hans Rosling: GapMinder: for a fact based world view
http://www.gapminder.org
Hans Rosling: Stats that shape your world view: TED Talk, Video
http://www.ted.com/talks/hans_rosling_shows_the_best_stats_you_ve_ever_seen.html?qtwh=true&utm_expid=166907-16
Ben Schneiderman
http://www.cs.umd.edu/~ben/
Edward Tufte
http://www.edwardtufte.com/tufte/
Flowing Data blog (Nathan Yau)
http://flowingdata.com and "Visualize This" e-book (Safari)
Cliff Atkinson
Beyond Bullet Points: Using MS PowerPoint to Create Presentations that Inform, Motivate and Engage e-book (Safari)
Garr Reynolds
Presentation zen design: simple design principles and techniques to enhance your presentations e-book (Safari)