You can download the old 2005 version of Leica Lens Compendium by Erwin Puts for free at this link. This 223 page version does not contain any images and it’s available as a free download with the permission of the author. Erwin Puts released a new new version of this book in August 2011.
Erwin Puts announced on his website that there will be a new version of the Leica Lens Compendium book which should be available shortly (this explains why the old version goes for over $1000on on eBay and on Amazon). Erwin Puts also published a 129 pages Leica Pocket Guide that can be downloaded for free here.
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