@article{JEDP_1989____A11_0,
     author = {Jensen, Arne},
     title = {Stark hamiltonians with periodic potentials},
     journal = {Journ\'ees \'equations aux d\'eriv\'ees partielles},
     eid = {11},
     pages = {1--6},
     publisher = {Ecole polytechnique},
     year = {1989},
     mrnumber = {1030826},
     language = {en},
     url = {http://archive.numdam.org/item/JEDP_1989____A11_0/}
}