@article{10_4064_sm153_1_2,
     author = {Wojciech M/lotkowski},
     title = {Operator-valued version of conditionally free product},
     journal = {Studia Mathematica},
     pages = {13--30},
     publisher = {mathdoc},
     volume = {153},
     number = {1},
     year = {2002},
     doi = {10.4064/sm153-1-2},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/sm153-1-2/}
}