Emission-line properties for PGC 28308. (a): η-parameter map. (b): velocity dispersion map. (c): logarithmic EW(Hα) map. The lower limit of the OB-star-dominated ionization (EW(Hα) = 14 Å) is contoured in black. (d)–(f): VO diagrams. The solid line is the Kewley et al. (2001) extreme starburst line, the dashed line in (d) is the Kauffmann et al. (2003) empirical starburst line, and the dash-dot lines in (e) and (f) are the Kewley et al. (2006) Seyfert and low-ionization narrow emission-line region (LINER) demarcation line. The colors in the VO diagrams correspond to the colors in the η-parameter map. While there is no clear biconical morphology in the η-parameter map, the concentration of the eDIG over the center of the galaxy could hint at ionization by outflow driven shocks. Similar figures for ESO 443−21 and PGC 28308 are found in Appendix B.