@article{Hansen_1987, title={Danske havne 1950-1980 John Westerholm: The Development of a National Port System - Denmark 1950-1980.}, volume={87}, url={https://tidsskrift.dk/geografisktidsskrift/article/view/44406}, journal={Geografisk Tidsskrift}, author={Hansen, Viggo}, year={1987}, month={jan.} }