@article{ZNSL_1975_50_a1,
     author = {P. P. Tammela},
     title = {On reduction theory of positive quadratic forms},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {6--96},
     year = {1975},
     volume = {50},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1975_50_a1/}
}