@article{IVM_1988_4_a10,
     author = {A. L. Teptin},
     title = {On the sign of the {Green} difference function},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {69--72},
     publisher = {mathdoc},
     number = {4},
     year = {1988},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1988_4_a10/}
}