Open J. Discrete Math. Vol.8 No.2, April 25, 2018 DOI:10.4236/ojdm.2018.82005
Open J. Discrete Math. Vol.8 No.2, April 20, 2018 DOI:10.4236/ojdm.2018.82004
Open J. Discrete Math. [ISSUE], [PUBDATE] DOI:[DOI]
