1. Armstrong M.L. Singh R. and Dennis M.L. (2014). Oregon Coordinate Reference System Handbook and User Guide v2.01 Oregon Department of Transportation ftp.odot.state.or.us/ORGN/Documents/ocrs_handbook_user_guide.pdf (Feb 8 2016).
2. Dean G. Oimoen M. Greenlee S. Nelson C. Steuck M. and Tyler D. (2002). The National Elevation Dataset Photo Eng & Rem Sens ASPRS 68 (1) www.asprs.org /a/publications/pers/2002journal/january/highlight.html (Feb 8 2016).
3. Dennis M.L. (ed.) (2014). Rocky Mountain Tribal Coordinate Reference System Handbook and User Guide v1.0 Rocky Mountain Tribal Transportation Association www.neciusa.com/documents/RMTCRS_Manual.pdf (Feb 8 2016).
4. Dennis M.L. Miller N. and Brown G. (2014). Iowa Regional Coordinate System Handbook and User Guide v2.10 Iowa Department of Transportation www.iowadot.gov/rtn/pdfs/IaRCS_Handbook.pdf (Feb 8 2016).
5. Dracup J.F. (1974). Fundamentals of the State Plane Coordinate Systems National Geodetic Survey www.ngs.noaa.gov/PUBS_LIB/FundSPCSys.pdf (Feb 8 2016).