A note on topological projective planes (Q810868)

The author proves a theorem on topological projective planes concerning topological properties hereditary to open subspaces and products. Corollary: In a topological projective plane the local connectedness, second countability, separability and first countability of (a) the space of points, (b) the space of lines, (c) a ray of points, (d) a ray of affine points, and (e) the set of points of an affine plane are all equivalent.