Relations between ß X / X and a Certain Subspace of ... X. Jan van Mill (1977) Mathematische Zeitschrift
Remarks on extremally disconnected semitopological groups Igor V. Protasov (2002) Commentationes Mathematicae Universitatis Carolinae Answering recent question of A.V. Arhangel'skii we construct in ZFC an extremally disconnected semitopological group with continuous inverse having no open Abelian subgroups.