[1] Blaszczyk A., Szymanski A.: Some nonnormal subspaces of the Čech-Stone compactifications of a discrete space. (1980), in: Proc. 8-th Winter School on Abstract Analysis, Prague.
[2] Dow A.: 
Remote points in spaces with $\pi $-weight $ømega _ 1$. (1984), 124 Fund. Math. 
MR 0774511 
[3] van Douwen E.K.: 
Why certain Čech-Stone remainders are not homogeneous. (1979), 41 Colloq. Math. 
MR 0550626 | 
Zbl 0424.54012 
[4] van Douwen E.K.: Remote points. (1988), 188 Dissert. Math.
[5] Gryzlov A.A.: 
On the question of hereditary normality of the space $\beta ømega \setminus ømega $. (1982), Topology and Set Theory (Udmurt. Gos. Univ., Izhevsk). 
MR 0760274 
[7] Logunov S.: 
On hereditary normality of zero-dimensional spaces. (2000), 102 Topology Appl. 
MR 1739263 | 
Zbl 0944.54016 
[8] van Mill J.: An easy proof that $\beta N \setminus N \setminus \{p\} $ is non-normal. (1984), 2 Ann. Math. Silesianea.
[9] Rajagopalan M.: 
$\beta N \setminus N \setminus \{p\} $ is not normal. (1972), 36 J. Indian Math. Soc. 
MR 0321012 
[10] Shapirovskij B.: On embedding extremely disconnected spaces in compact Hausdorff spaces, b-points and weight of pointwise normal spaces. (1987), 223 Dokl. Akad. Nauk SSSR.