Biographies of Mathematicians: Marin Mersenne: Reviews his life and mathematical contributions.
Catalog of the Scientific Community: Mersenne, Marin: Basic biographical facts compiled as part of the Galileo Project.
Catholic Encyclopedia: Marin Mersenne: Article by C.A. Dubray reviewing the intellectual career of this learned Minim friar.
Horror Vacui? Marin Mersenne: Brief article focusing on Mersenne's role in the early scientific debate on this problem of the vacuum.
Luke's Marin Mersenne Page: A collection of pages and links concerned with this philosopher, mathematician and scientist.
Marin Mersenne: Biography of the Minim friar and his contributions to number theory. Includes references, pictures, and cross-references to other topics.
Marin Mersenne: Concise biography.
The Bassoons in Marin Mersenne's Harmonie universelle: Scholarly paper by Richard Semmens, reconstructing the history of early modern woodwind instruments with reference to Mersenne's text.
Wikipedia: Marin Mersenne: Entry from this openly-edited online reference tool.