射影面束 projective pencils of planes

射影平面 [数] projective plane ; [数] plane of projection

复射影平面 [数] complex projective plane

实射影平面 [数] real projective plane

球极平面射影 [测] [数] stereographic projection

心射切面投影 [晶体] gnomonic projection

射影极小曲面 [数] projective minimal surface

极射赤面投影 stereographic projection

射影二次曲面 projective quadric