@article{SIGMA_2006_2_a40,
     author = {Vladimir P. Burskii and Alexei S. Zhedanov},
     title = {Dirichlet and {Neumann} {Problems} for {String} {Equation,} {Poncelet} {Problem} and {Pell{\textendash}Abel} {Equation}},
     journal = {Symmetry, integrability and geometry: methods and applications},
     year = {2006},
     volume = {2},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SIGMA_2006_2_a40/}
}