http://www.cadforum.cz/catalog_en/
http://www.cadyou.com/cad-blocks
http://www.archinoah.com/cad_caad_model_library/cad-objects.html
http://3dmodelsharing.aeccafe.com/index.php
http://www.us.kohler.com/us/CAD-&-Cutout-Symbols/content/CNT300084.htm
http://www.tracepartsonline.net/(S(ainujh45msnkgz45ksex3s45))/content.aspx
http://www.cadblocos.arq.br/index.html
http://www.doschdesign.com/productlist2.php?line=4&sortorder=2
http://www.polantis.com/free3Dmodel/utilities