I am looking for references discussing the space of graphs G=(V,E), attempts at definition of distance between graphs, proximity, small (differential) neighborhoods of distinct graphs (different number of vertices in particular), transformations etc., references akin to this paper:
https://www.sciencedirect.com/science/article/pii/S0166218X16303067
I am finding the discussion and references on space of graphs (w distinct number of nodes) surprisingly illusive. Suggestions, or comments would be greatly appreciated.