For people who don’t understand graphs, Euler graphs seem like such a weird place to start. There are much more relevant problems (social networks, followers and travel distances) with approachable graphs (undirected, directed, and weighted).
The Nature of Computation - Moore, Mertens
What I got (graduate coursework):
Graph Theory - Reinhard Diestel
A more encyclopedic treatment (most big results, no proofs):
Handbook of Graph Theory - Gross, Yellen
What do you mean by 'Euler graphs'? As in, the problems described by him such as the bridge problem?
I would call anything with vertices and edges an 'Euler graph' as opposed to a 'Cartesian graph' (a chart).
He specifically mentions in the article that he found both terms and used the one used in the literature he refers to.
> I used “Euler path” instead of “Eulerean path” just to be consistent with the referenced book [1] definition
Should be 'Eulerian'. It's not horribly confusing, just a little vague.