On what basis do you claim that software engineering is not part of computer science? Those papers were all written by professors of computer science and published in journals of computer science. All were cited many times by other papers written by other professors of computer science in other journals of computer science.
Software engineering is taught as a part of the field that's called computer science, but the original question was about whether the field called computer science is actually a science.
I guess the difference in that regard would be that (software) engineering doesn't necessarily follow the formal scientific method of formulating a hypothesis and then testing it experimentally. That would, in some sense, make it distinct from science. The same would practically apply to many areas in computer science that are studied experimentally, not just software engineering.
To elaborate on that a little, (software) engineering does build on experience and empiricism, as well as analytical thinking, but in practice it may be more in the form of "lessons learned" than in the form of hypothesis testing.
That doesn't make it any less valuable, or even any less valid as an academic area of research. It just, in some sense, makes it possibly distinct from the sciences.
Of course there are also problems in CS that can actually be studied with the scientific method, but I think amelius might have meant that publications such as Dijkstra's and Knuth's papers on goto would be more in the "lessons learned" category than in the "results from the scientific method" category. They would thus not really make computer science a science even though they're not really in the "CS as a part of math" category either.
