normals - Disable double sided faces in Blender 3D View - Blender Stack Exchange
Is it better to have models that have double faces or is it better to have a two-sided material instead? - Pipeline & Plugins - Epic Developer Community Forums
What is wrong with my Normals? - #17 by dark_minaz - Support - Sketchfab Forum
Turn off double-sided faces for sculpting... - Modeling - Blender Artists Community
Blender Sushi: RENDER / Wired & Double-Sided Useful Material Tricks