@article{1178242593, author = {Spencer, Christopher B.}, title = {Relative homotopy operations}, journal = {Tohoku Math. J. (2)}, volume = {23}, number = {4}, year = {1971}, pages = { 453-456}, language = {en}, url = {http://dml.mathdoc.fr/item/1178242593} }
Spencer, Christopher B. Relative homotopy operations. Tohoku Math. J. (2), Tome 23 (1971) no. 4, pp. 453-456. http://gdmltest.u-ga.fr/item/1178242593/