In mathematics, a bouquet graph , for an integer parameter , is an undirected graph with one vertex and edges, all of which are self-loops. It is the graph-theoretic analogue of the topological bouquet, a space of circles joined at a point. When the context of graph theory is clear, it can be called more simply a bouquet. In graph-theoretic approaches to group theory, every Cayley–Serre graph (a variant of Cayley graphs with doubled edges) can be represented as the covering graph of a bouquet.