World Wide School
World Wide School: Chapter Iii: The Empress Dowager as a Ruler
This is a chapter from the book, "Court Life in China: The Capital - Its Officials and People" by Isaac Taylor Headland. It contains an interesting look at the power that Empress Dowager Cixi held in China.
Other
Kings College: Tzu Hsi: The Dowager Empress of China
This is an informative piece about Empress Dowager Cixi and her rise to power in China. It contains an excellent bibliography with further research sources.