@article{2650,
author = {Saalfrank, C.W.},
title = {Contractibility and a generalization of absolute extensor},
journal = {Portugaliae mathematica},
volume = {30},
year = {1971},
pages = {71-72},
zbl = {0226.54014},
mrnumber = {0303499},
language = {en},
url = {http://dml.mathdoc.fr/item/2650}
}
Saalfrank, C.W. Contractibility and a generalization of absolute extensor. Portugaliae mathematica, Tome 30 (1971) pp. 71-72. http://gdmltest.u-ga.fr/item/2650/