Open J. Discrete Math. Vol.7 No.4, October 31, 2017 DOI:10.4236/ojdm.2017.74018
Open J. Discrete Math. Vol.7 No.4, September 13, 2017 DOI:10.4236/ojdm.2017.74017
Open J. Discrete Math. [ISSUE], [PUBDATE] DOI:[DOI]