@ARTICLE{PardalEtal:jaesa08,
  title = {Study of Orbital Elements on the Neighbourhood of a Frozen Orbit},
  author = {Paula Cristiane Pinto Mesquita Pardal and Hélio Koiti Kuga and Rodolpho Vilhena de Moraes},
  pages = {23--32},
  journal = {Journal of Aerospace Engineering, Sciences and Applications},
  volume = {1},
  number = {2},
  year = {2008}
}