http://tti.tamu.edu/documents/0-6103-1.pdf
http://www.ntis.gov
http://mutcd.fhwa.dot.gov/
http://www.dot.ca.gov/hq/traffops/signtech/mutcdsupp/ca_mutcd2010.htm
http://www.sha.maryland.gov/OOTS/09ReducedChannelizingDeviceSpacing.pdf
http://www.dot.state.fl.us/rddesign/rd/rtds/08/2008Standards.shtm
http://mutcd.fhwa.dot.gov/
http://www.txdot.gov/txdot_library/publications/tmutcd.htm
http://www.dot.state.tx.us/insdtdot/orgchart/cmd/cserve/standard/toc.htm
http://www.aashtotf13.org/
http://safety.fhwa.dot.gov/roadway_dept/policy_guide/road_hardware/wzd/
http://ftp.txdot.gov/pub/txdot-info/trf/pdf/cwztcd.pdf
http://wwwnrd.nhtsa.dot.gov/pdf/esv/esv19/05-0450-O.pdf
http://www.fhwa.dot.gov/policy/ohim/hs05/htm/dl22.htm
http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_400.pdf
http://onlinemanuals.txdot.gov/txdotmanuals/rdw/rdw.pdf