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The UTR-2 Very Low Frequency Sky Survey and Its Main Results

During the past decade there has been a dramatic increase in the amount of high-frequency (v > 1000 MHz) data currently underlying the studies of bright compact sources (T b ~ 1011-12 K, l ≤ 1 kpc) with flat spectra. But in order to determine physical conditions inside extragalactic radio sources at different stages of their evolution the studies of old extended (l ~ 100 kpc) sources with low surface brightness and steep spectra which constitute the dominant radio source population at very low frequencies (v 《 100 MHz) are also needed. These sources are known to represent the final stage in the evolution of extragalactic objects.