@article{10_1090_S0894_0347_09_00644_4,
     author = {Popa, Sorin and Vaes, Stefaan},
     title = {Actions of {\dh}”{\textonehalf}_{\^aˆž} whose {II\^a‚} factors and orbit equivalence relations have prescribed fundamental group},
     journal = {Journal of the American Mathematical Society},
     pages = {383--403},
     publisher = {mathdoc},
     volume = {23},
     number = {2},
     year = {2010},
     doi = {10.1090/S0894-0347-09-00644-4},
     url = {http://geodesic.mathdoc.fr/articles/10.1090/S0894-0347-09-00644-4/}
}