Composite image of the Leo A galaxy: Subaru/Suprime-Cam Hα (red) and B (green) passbands and the H I column density map (blue) with cyan contours, indicating the range of column density levels (atoms cm⁻²) from 4 × 10²⁰ to 7 × 10²¹ with a constant step of 10²⁰ (Hunter et al. 2012). The straight cyan line divides the largest H I hole into two regions with apparently different stellar populations. Positions and sizes of three small holes in the H I envelope, identified by Pokhrel et al. (2020), are indicated with cyan circles.