@article{bdnsz-pttp-10
, author = {Pankaj Agarwal and Sergey Bereg and Ovidiu Daescu and Haim Kaplan
and Simeon Ntafos and Micha Sharir and Binhai Zhu}
, title = {Guarding a Terrain by Two Watchtowers}
, journal = {Algorithmica}
, year = {2010}
, volume = {58}
, number = {2}
, pages = {352--390}
, url = {http://dx.doi.org/10.1007/s00453-008-9270-3}
}