[en] Electron densities in laser-produced plasmas have been deduced from space-resolved spectra of oxygen-like ions CaXIII, TiXV, FeXIX, NiXXI and CuXXII in the xuv (80-170 A). The transition 2p61Ssub(o) → 2s2p51P1 has been identified for CuXXII, the wavelength of the same transition for NiXXI has been defined more precisely. Plasma images in the light of different spectral lines have yielded the dimensions of the spacial regions in which CaXIII, FeXIX and NiXXI exist. (author)