@article{700608,
     title = {Embeddable spaces and duality 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 = {[361]-366},
     mrnumber = {MR0514984},
     zbl = {0374.18004},
     url = {http://dml.mathdoc.fr/item/700608}
}

Porst, H.-E. Embeddable spaces and duality in topological categories, dans General topology and its relations to modern analysis and algebra IV, GDML_Books,  (1977), pp. [361]-366. http://gdmltest.u-ga.fr/item/700608/