@article{GDZPPN002062011, title = {Compact Quadratic s-Manifolds}, journal = {Commentarii mathematici Helvetici}, volume = {51}, year = {1976}, pages = {105-132}, zbl = {0323.53038}, url = {http://dml.mathdoc.fr/item/GDZPPN002062011} }
Ledger, Arthur J.; Pettitt, R. Bruce. Compact Quadratic s-Manifolds. Commentarii mathematici Helvetici, Tome 51 (1976) pp. 105-132. http://gdmltest.u-ga.fr/item/GDZPPN002062011/