The major contending scenarios capable of explaining various aspects of the Seyfert phenomenon in AGNs are (i) the Super-massive Black-Hole model and (ii) the Starburst model. Detailed optical emission-line and radio images of Seyfert nuclei, and their mutual correlations, provide important clues in evaluating the claims of each. Using the EVN at λ 18 cm, we have mapped four Seyfert galaxies, Mkn 1, 3, 231 and 463 at a resolution of ∼ 25 mas. The maps, and comparisons with images at other wavelengths, will be presented elsewhere (Ghosh et al. 1993, in preparation). Here, we present parameters derived from elliptical-Gaussian fits to all discernible components (Table 1).