Leica APO-Summicron-M 50mm f/2 ASPH Lens by Leica at B&C Camera
Leica APO-Summicron-M 50mm f/2 ASPH. Lens 11811 B&H Photo Video
Leica 50mm APO-Summicron-M ASPH f/2.0 review, sampel photos and interview with the lens designer Peter Karbe - Thorsten Overgaard's Leica Photography Pages
Official: Voigtlander 50mm f/2 APO VM mount - FM Forums
Leica unveils retro version of the APO-Summicron-M 50mm F2.0 ASPH to honor the LHSA: Digital Photography Review