@article{EJDE_2012__2012__a81,
     author = {Gil',  Michael I.},
     title = {Sums of zeros of solutions to second order {ODE} with non-polynomial coefficients},
     journal = {Electronic journal of differential equations},
     year = {2012},
     volume = {2012},
     zbl = {1260.34162},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_2012__2012__a81/}
}