TY CONF TI Regular distribution of star formation regions along the spiral arms and rings of disk galaxies KW HII regions; galaxies: star clusters: general; galaxies: ISM KW spiral KW star formation JO Modern astronomy: from the Early Universe to exoplanets and black holes AU Gusev, A.. AU Shimanovskaya, E.. PY 2024 PB Special Astrophysical Observatory of the Russian Academy of Sciences