R Ponraj, R Singh, SS Narayanan - Palestine Journal of …, 2017 - researchgate.net
Let G be a (p, q) graph. Let f be an injective map from V (G) to {1, 2,..., p}. For each edge xy,
assign the label (xy) or (yx) according as x> y or y> x. f is called a parity combination cordial …