International Mountain Biking Association (IMBA): http://www.imba.com/
Oregon Bicycle Racing Association (ORBA): http://obra.org/
Oregon Enduro Racing Series: http://oregonenduro.com/
Hood River County Recreation Trails: http://www.co.hood-river.or.us/index.asp?Type=B_BASIC&SEC={0D9E9729-161D-4FA2-801F-8735B547071D}
