I did not find a PDF of this paper but Schrijver ( 2012 ) summarizes it well: For unit-cost graphs it presents an \(O(m)\) BFS algorithm, and for general weighted graphs an \(O(mn)\) algorithm. Dijkstra (1959) introduces the classic \(O(n^2)\) algorithm of repeatedly expanding the open vertex with shortest distance from the start (using more modern terminology), and recommends storing the shortest distance to each node together with the node. This was later improved to \(O(n\lg n)\) using e.g. a priority queue.