We extend the definition of edge-cordial graphs due to Ng and Lee for graphs on \(4k\), \(4k+1\), and \(4k+3\) vertices to include graphs on \(4k+2\) vertices, and show that, in fact, all graphs without isolated vertices are edge-cordial. Ng and Lee conjectured that all graphs on \(4k\), \(4k+1\), or \(4k+3\) vertices are edge-cordial.
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