@unpublished{HovhannisyanSchulze2010,
  author    = {Hovhannisyan, A. H. and Schulze, Bert-Wolfgang},
  title     = {On a method for solution of the ordinary differential equations connected with Huygens' equations},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-45381},
  year      = {2010},
  language  = {en}
}