(1)
Abramian, M. G.; Harutyunian, S. V. ABOUT THE MARGINAL IN STABILITY OF SELFGRAVITATING RING. Proc. YSU A: Phys. Math. Sci. 2000, 34 (2 (193), 47-51. https://doi.org/10.46991/PYSUA.2000.34.2.047.