@article{GDZPPN002412691, title = {Massey Products and H (p, q)-Systems.}, journal = {Mathematische Zeitschrift}, volume = {135}, year = {1973}, pages = {1-10}, zbl = {0249.55018}, url = {http://dml.mathdoc.fr/item/GDZPPN002412691} }
Davis, Donald M.; Snaith, Victor P. Massey Products and H (p, q)-Systems.. Mathematische Zeitschrift, Tome 135 (1973) pp. 1-10. http://gdmltest.u-ga.fr/item/GDZPPN002412691/