Some Dense Barrelled Subspaces of $\omega$ and Incomplete $\phi$-Spaces.

Catalan, F. X., & Tweddle, I. (1994). Some Dense Barrelled Subspaces of $\omega$ and Incomplete $\phi$-Spaces. MATHEMATICA SCANDINAVICA, 75, 185–194. https://doi.org/10.7146/math.scand.a-12514