Sigma 17-50mm f/2.8 EX DC OS HSM Lens - Black Lab Imaging
Sigma 17-50mm F2.8 EX DC OS HSM Nikon - DXOMARK
Amazon.com : Sigma 17-50mm f/2.8 EX DC OS HSM Zoom Lens for Nikon DSLRs with APS-C Sensors + Deal Expo Accessories Bundle : Electronics
Amazon.com : Sigma 17-50mm f/2.8 EX DC OS HSM FLD Large Aperture Standard Zoom Lens for Nikon Digital DSLR Camera - International Version (No Warranty) : Electronics