Interstellar Filaments and the Statistics of Galactic HI
  This paper presents a statistical explanation of filament formation in the galactic atomic hydrogen. Recently developed technique allows to determine the 3D spectrum of random HI density. We claim that even in the absence of dynamical factors the Gaussian field corresponding to the measured values of the spectrum of HI density should exhibit filamentary structure, the existence of which has long been claimed. 
Alex Lazarian and Dmitri Pogosyan