Just what do we have in mind when we talk about the Berlin problem? A moment's thought makes it clear that it is not one problem, but a number of closely interrelated problems.
"The Historical and Geopolitical Aspects of the Berlin Crisis,"
Naval War College Review: Vol. 14
, Article 3.
Available at: https://digital-commons.usnwc.edu/nwc-review/vol14/iss8/3