Vietnam Journal of Mathematics
Vietnam Journal of Mathematics > 2013 > 41 > 3 > 341-352
Vietnam Journal of Mathematics > 2013 > 41 > 3 > 353-366
Vietnam Journal of Mathematics > 2013 > 41 > 3 > 323-331
Vietnam Journal of Mathematics > 2014 > 42 > 2 > 219-232
Vietnam Journal of Mathematics > 2014 > 42 > 2 > 205-218
Vietnam Journal of Mathematics > 2015 > 43 > 3 > 621-627
Vietnam Journal of Mathematics > 2015 > 43 > 4 > 777-792
Vietnam Journal of Mathematics > 2016 > 44 > 3 > 637-648