@article{TRSPY_2006_255_a2,
     author = {H. Begehr and Vu Thi Ngoc Ha and Zh. Zhang},
     title = {Polyharmonic {Dirichlet} {Problems}},
     journal = {Informatics and Automation},
     pages = {19--40},
     year = {2006},
     volume = {255},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TRSPY_2006_255_a2/}
}