@article{ZNSL_1986_151_a12,
     author = {P. P. Tammela},
     title = {On the theory of the reduction of positive quadratic forms. {Abnormality} of the partition of the positivity cone into the {Minkowski} $(n\geqslant7)$ and {Barns--Cohn} reduction regions $(n=4)$.},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {125--134},
     publisher = {mathdoc},
     volume = {151},
     year = {1986},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1986_151_a12/}
}