The Arduino Micro, referenced on http://arduino.cc/en/Main/arduinoBoardMicro#.UxKEZf00PfM, clicking to view the pinout, takes you to this graphic:
comparing the proc documentation and the actual information on the chip with the pinout graphic, pins A9 through A11 are mis-marked on the image. A8 is missing altogether, and there's an imaginary A12 to make up the difference. ("A6 trough A11 are shared respectively on digital pins 4, 6, 8, 9, 10, and 12.", maybe a "SIC" on "trough" too unless you're Canadian ;)
I didn't see any specific forum for posting bugs on the web site / documentation, so if this is in the wrong forum, please tell me where to move it, or move it yourself if you can, I'm pretty new to the Arduino forums.
Summary of correction needed: change "A9" to "A8". Change "A10" to "A9". Change "A11" to "A10". Change "A12" to "A11". If you've lost the original, I can probably PS you up a corrected png if you need one.