@article{GDZPPN002430452, title = {The Hasse-Witt Matrix of a Formal Group.}, journal = {Mathematische Zeitschrift}, volume = {189}, year = {1985}, pages = {151-166}, zbl = {0535.14021}, url = {http://dml.mathdoc.fr/item/GDZPPN002430452} }
Kneppers, Harry A.W.M. The Hasse-Witt Matrix of a Formal Group.. Mathematische Zeitschrift, Tome 189 (1985) pp. 151-166. http://gdmltest.u-ga.fr/item/GDZPPN002430452/