Partial solution is given here respect to one open problem posed by P. Fletcher and W. F. Lindgren in their monography Quasi-uniform spaces.
@article{urn:eudml:doc:39280, title = {On some questions in quasi-uniform topological spaces.}, journal = {Stochastica}, volume = {13}, year = {1992}, pages = {37-42}, zbl = {0778.54016}, mrnumber = {MR1197326}, language = {en}, url = {http://dml.mathdoc.fr/item/urn:eudml:doc:39280} }
Ferrer Llopis, Jesús; Gregori Gregori, Valentín; Alegre Gil, Carmen. On some questions in quasi-uniform topological spaces.. Stochastica, Tome 13 (1992) pp. 37-42. http://gdmltest.u-ga.fr/item/urn:eudml:doc:39280/