Keywords: Patent-Document-2967578.jpg US Patent 2967578 BadJPEG PD-USGov original upload log page en wikipedia Patent-Document-2967578 jpg 2007-02-24 05 22 Melensdad 500×490×8 68359 bytes <nowiki></nowiki> 2007-02-24 05 01 Melensdad 500×490×8 55612 bytes <nowiki>US Patent 2967578</nowiki> Snowmobiles |