Atlases

Link to RTOG Contouring Atlas:

http://www.rtog.org/CoreLab/ContouringAtlases.aspx

The above link is currently not working due to reconstruction of that website per info at: https://www.rtog.org

However it does provide a new link:
https://www.nrgoncology.org/About-Us/Center-for-Innovation-in-Radiation-Oncology

Link to University of Michigan GI Atlas:

http://www.med.umich.edu/radonc/education/ContourAtlas/index.htm