@article{GDZPPN002413310, title = {On Internal Formation Theory.}, journal = {Mathematische Zeitschrift}, volume = {135}, year = {1973}, pages = {1-10}, zbl = {0272.20011}, url = {http://dml.mathdoc.fr/item/GDZPPN002413310} }
Wright, Charles R.B. On Internal Formation Theory.. Mathematische Zeitschrift, Tome 135 (1973) pp. 1-10. http://gdmltest.u-ga.fr/item/GDZPPN002413310/