Naval War College Review
This is an excerpt from a research paper in which Colonel Dodenhoff quite exhaustively examines the employment of mercenaries.
Dodenhoff, George H.
"The Congo: A Case Study of Mercenary Employment,"
Naval War College Review: Vol. 22:
4, Article 6.
Available at: https://digital-commons.usnwc.edu/nwc-review/vol22/iss4/6