Steve Tufte's PhD Thesis
The WHAM Spectrometer: Design, Performance Characteristics, and First Results
Note: I recommend getting the ps files if you can handle them. The pdf files were made from the ps files and don't look so good on the screen (though they do print fine).
By Chapter...
Title Page and Table of Contents (ps, pdf)
Chapter 1 - Introduction (ps, pdf)
Chapter 2 - The WHAM Spectrometer: Theory and Design (ps, pdf)
Chapter 3 - The WHAM Spectrometer: Performance Characteristics (ps, pdf)
Chapter 4 - WHAM Observations of Emission Lines from HVCs in the M Complex (ps, pdf)
Chapter 5 - Detection of the He I 5876 Recombination Line from the WIM with the WHAM Spectrometer (ps, pdf)