Some characterizations of bitopological QHC-spaces (Q686213)

A bitopological space \((X,\tau_ 1,\tau_ 2)\) is defined to be pairwise QHC if every \(\tau_ j\)-open filterbase in \(X\) has a \(\tau_ i\)- adherent point, for \(i,j=1,2\) and \(i\neq j\). This class of spaces has been studied by \textit{Ch. G. Kariofillis} [Ann. Soc. Sci. Brux. Ser. I 100, 129-137 (1986; Zbl 0659.54026)]. Several characterizations of this class of spaces, in terms of the bitopological analogues of weakly continuous functions and strongly closed and \(\theta\)-closed graph functions, are provided in the paper under review.