@article{BMMS_1999_22_2_a6,
     author = {Wong Peng Choon and Gan Hui Woan},
     title = {Cyclic {Subgroup} {Separability} of {Certain
}                        {HNN} {Extensions}},
     journal = {Bulletin of the Malaysian Mathematical Society},
     year = {1999},
     volume = {22},
     number = {2},
     url = {http://geodesic.mathdoc.fr/item/BMMS_1999_22_2_a6/}
}