@article{10_4064_sm218_1_3,
     author = {Antonio J. Guirao and Olena Kozhushkina},
     title = {The {Bishop{\textendash}Phelps{\textendash}Bollob\'as} property for
 numerical radius in $\ell _{1}(\mathbb {C})$},
     journal = {Studia Mathematica},
     pages = {41--54},
     publisher = {mathdoc},
     volume = {218},
     number = {1},
     year = {2013},
     doi = {10.4064/sm218-1-3},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/sm218-1-3/}
}