Filaments of the Helix NebulaVorontsov-Velyaminov, B.A.Cambridge University Press1968DOI 10.1017/s0074180900020660
Helix Nebula Displays Hundreds of Gaseous KnotsGloria B. LubkinPhysics Today1996DOI 10.1063/1.2807648
Morphology and Composition of the Helix NebulaHenry, R. B. C.University of Chicago Press1999DOI 10.1086/307215
A New Extension Of The Helix NebulaG. ARAYA, V. M. BLANCO and M. G. SMITHUniversity of Chicago Press1972DOI 10.2307/40675182
Highly Polarized Counterpart Of The Double Helix NebulaTsuboi, MasatoUniversity of Chicago Press2010DOI 10.1088/2041-8205/719/2/l177
Fractal Analysis of the Helix Nebula (NGC 7293)Srabani DattaCambridge University Press2003DOI 10.1017/s0074180900209558
Unraveling the Helix Nebula: Its Structure and KnotsO'Dell, C. R.The Astronomical Journal2004DOI 10.1086/424621