Terrain
Rendering Terrain using Chunked LOD Control
http://tulrich.com/geekstuff/sig-notes.pdf
Real-Time Continuous Level-of-Detail Terrain Rendering With Nested Splitting Space
http://www.people.fas.harvard.edu/~yzhu/doc/isef2k1-paper.pdf
Geometry Clipmaps: Terrain Rendering Using Nested Regular Grids
http://research.microsoft.com/en-us/um/people/hoppe/geomclipmap.pdf
Terrain Tessellation
http://developer.download.nvidia.com/assets/gamedev/files/sdk/11/TerrainTessellation_WhitePaper.pdf