Density of a family of linear varietes Grazia Raguso, Luigia Rella (2006) Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica The measurability of the family, made up of the family of plane pairs and the family of lines in 3 -dimensional space A 3 , is stated and its density is given.
Determination of compact subsets from functionals on them. Stepanov, V.N. (2005) Sibirskie Ehlektronnye Matematicheskie Izvestiya [electronic only]
Differential Topology and the Computation of Total Absolute Curvature. Eberhard Teufel (1981) Mathematische Annalen