@article{MZ_1963__82_170178,
     author = {B. Eckman and P.J. Hilton},
     title = {A natural transformation in homotopy theory and a theorem of {G.W.} {Whitehead.}},
     journal = {Mathematische Zeitschrift},
     pages = {115--124},
     publisher = {mathdoc},
     volume = {82},
     year = {1963},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/MZ_1963__82_170178/}
}