Umarin Pintoptang. 2001. Some sufficient conditions for cyclic trajectories in a two-dimensional analog of the 3x+1 problem. Department of Mathematics, Chulalongkorn University;
Umarin Pintoptang. (2001) Some sufficient conditions for cyclic trajectories in a two-dimensional analog of the 3x+1 problem . Chulalongkorn University/Bangkok.
Umarin Pintoptang. Some sufficient conditions for cyclic trajectories in a two-dimensional analog of the 3x+1 problem. . Bangkok:Chulalongkorn University, 2001.
Umarin Pintoptang. (2001) Some sufficient conditions for cyclic trajectories in a two-dimensional analog of the 3x+1 problem . Chulalongkorn University/Bangkok.