@article{JMAG_2009_5_1_a1,
     author = {R. Almeida and V. Neves and A. Plakhov},
     title = {Retroreflecting curves in nonstandard analysis},
     journal = {\v{Z}urnal matemati\v{c}eskoj fiziki, analiza, geometrii},
     pages = {12--24},
     year = {2009},
     volume = {5},
     number = {1},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/JMAG_2009_5_1_a1/}
}