@ARTICLE{Balcerzak_Jerzy_Indicator_2002,
 author={Balcerzak, Jerzy and Panasiuk, Jan},
 volume={vol. 51},
 number={No 4},
 journal={Geodesy and Cartography},
 pages={171-176},
 howpublished={online},
 year={2002},
 publisher={Commitee on Geodesy PAS},
 abstract={In theory of regular projection of a surface into another surface, the term of the indicator of projection deformations, as a topological substitute of an infinitesimal circle of a unit radius is known. In the case of regular projection of a three-dimensional space into a three-dimensional space, a three-axis ellipsoid is the indicator of projection deformations, being the topological substitute of an infinitesimal unit sphere. This paper presents the attempt to analytically describe the infinitesimal unit sphere in the original space and its topological substitute in the projected space.},
 type={Article},
 title={Indicator of deformations of mutual projection of two arbitrary, regular, three-dimensional spaces},
 URL={http://journals.pan.pl/Content/121494/PDF/3_GK_TOM_LI_ZESZYT_4_2002_Balcerzak_Wskaznica.pdf},
}