Monographs are graph-like structures with directed edges of unlimited length that are freely adjacent to each other. The standard nodes are represented as edges of length zero. They can be drawn in a way consistent with standard graphs and many others, like E-graphs or $\infty$-graphs. The category of monographs share many properties with the categories of graph structures (algebras of monadic many-sorted signatures), except that there is no terminal monograph. It is universal in the sense that its slice categories (or categories of typed monographs) are equivalent to the categories of graph structures. Type monographs thus emerge as a natural way of specifying graph structures. A detailed analysis of single and double pushout transformations of monographs is provided, and a notion of attributed typed monographs generalizing typed attributed E-graphs is analyzed w.r.t. attribute-preserving transformations.

翻译：专题图是一种具有无界长度有向边且能自由邻接的图结构。标准节点被表示为长度为零的边。它们可以以与标准图及许多其他结构（如E-图或$\infty$-图）一致的方式绘制。专题图范畴与图结构范畴（一元多类签名的代数）共享许多性质，但不存在终对象原型。该范畴具有普适性，其切片范畴（或类型化专题图范畴）等价于图结构范畴。因此，类型化专题图自然地成为描述图结构的方法。本文对专题图的单推与双推变换进行了详细分析，并研究了一种泛化类型化属性E-图的属性型专题图概念，特别关注保留属性的变换。