@article{GMJ_2003__10_1_51558,
     author = {Rach\r{u}nkov\'a, Irena and Stan\v{e}k, Svatoslav},
     title = {Sturm-Liouville and focal higher order {BVPs} with singularities in phase variables.},
     journal = {Georgian mathematical journal},
     pages = {165--191},
     year = {2003},
     volume = {10},
     number = {1},
     zbl = {1069.34029},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/GMJ_2003__10_1_51558/}
}