@article{IVM_1975_2_a12,
     author = {F. K. Zakirov},
     title = {Solutions that are finally of constant sign for nonlinear differential equations with lag},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {108--111},
     publisher = {mathdoc},
     number = {2},
     year = {1975},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1975_2_a12/}
}