@article{PORMA_2006__63_1_52936,
     author = {Xu, Zhiting},
     title = {Averaging technique and oscillation for even order damped delay differential equations.},
     journal = {Portugaliae mathematica},
     pages = {23--36},
     year = {2006},
     volume = {63},
     number = {1},
     zbl = {1103.34058},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PORMA_2006__63_1_52936/}
}