@article{CMJ_2010_60_2_a3,
     author = {Martini, Horst and Spirova, Margarita},
     title = {A new type of orthogonality for normed planes},
     journal = {Czechoslovak Mathematical Journal},
     pages = {339--349},
     year = {2010},
     volume = {60},
     number = {2},
     mrnumber = {2657953},
     zbl = {1224.46026},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMJ_2010_60_2_a3/}
}