The way the section was phrased (it's removed now) it appeared to refer to some external source. The sentence "It is understood that the problems to follow shou

The way the section was phrased (it's removed now) it appeared to refer to some external source. The sentence "It is understood that the problems to follow should be taken in order, and begin with a statement of the original problem:" would make no sense otherwise. But if there is such an external source, it should be cited. This is the main problem. It's not about Wikipedia being a boring stickler for rules.