@article{700650,
     title = {Wallman extendible functions with normal domains},
     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 = {154-155},
     mrnumber = {MR0461413},
     zbl = {0375.54017},
     url = {http://dml.mathdoc.fr/item/700650}
}

Hajek, D. W. Wallman extendible functions with normal domains, dans General topology and its relations to modern analysis and algebra IV, GDML_Books,  (1977), pp. 154-155. http://gdmltest.u-ga.fr/item/700650/