@article{01305713,
title = {Higher homotopy groupoids and Toda brackets.},
journal = {Homology, Homotopy and Applications},
volume = {1},
year = {1999},
pages = {117-134},
zbl = {1002.55011},
language = {en},
url = {http://dml.mathdoc.fr/item/01305713}
}
Hardie, K.A.; Kamps, K.H.; Kieboom, R.W. Higher homotopy groupoids and Toda brackets.. Homology, Homotopy and Applications, Tome 1 (1999) pp. 117-134. http://gdmltest.u-ga.fr/item/01305713/