@article{700676,
     title = {Relative connectednesses and disconnectednesses in topological categories},
     booktitle = {General topology and its relations to modern analysis and algebra IV},
     series = {GDML\_Books},
     publisher = {Society of Czechoslovak Mathematicians and Physicist},
     address = {Praha},
     year = {1977},
     pages = {367-370},
     mrnumber = {MR0478107},
     zbl = {0371.54039},
     url = {http://dml.mathdoc.fr/item/700676}
}

Preuß, Gerhard. Relative connectednesses and disconnectednesses in topological categories, dans General topology and its relations to modern analysis and algebra IV, GDML_Books,  (1977), pp. 367-370. http://gdmltest.u-ga.fr/item/700676/