Lyα peak separation versus the observed Lyα luminosity of a compilation of star-forming LAEs. COLA1 (blue pentagon) has the lowest peak separation known, while NEPLA4 (dark blue diamond; Songaila et al. 2018) is the most luminous LAE known with a double peak. While there is no clear relation between the peak separation and Lyα luminosity at z ≈ 2 − 3 (orange star: luminous LAE C-147 at z = 2.23, that is shown in Fig. 6; green squares: points based on published results from Yamada et al. 2012 and Saez et al. 2015; magenta diamond: a low mass M_star <  10⁷ M_⊙ compact LAE presented in Vanzella et al. 2016), a clear anti-correlation is seen between peak separation and luminosity for Lyα emitting Green Pea galaxies (GPs; red points, Yang et al. 2017). This anti-correlation may be a selection effect, as GPs are selected on compactness and strong [OIII]/[OII] ratios that may trace density bounded HII regions, and not a pure Lyα selection.