A semi-double graph is a connected multi-graph such that each multi-edge consists of two edges. If there is at most one loop at each vertex of a semi-double graph, then this graph is called a single-petal graph. Via the degree-sum of nonadjacent vertices, the up-embeddability of semi-double graphs and single-petal graphs are discussed in this paper. And the results obtained in this paper can be extended to determine the up-embeddability of multi-graphs and pseudographs.
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