@article{MOMA_1971__75_177566,
     author = {Hugo, Jr. Teufel},
     title = {Second {Order} {Nonlinear} {Oscillation} - {Deviating} {Arguments.}},
     journal = {Monatshefte f\"ur Mathematik},
     pages = {341--345},
     publisher = {mathdoc},
     volume = {75},
     year = {1971},
     zbl = {0204.40802},
     url = {http://geodesic.mathdoc.fr/item/MOMA_1971__75_177566/}
}