Hohnston, R., & Morgan, W. P. Spatial Structures. Introducing the study of spatial systems in human geography. Methuen.
Chicago-viite (17. p.)Hohnston, R.J, ja W.B. Pugh Morgan. Spatial Structures. Introducing the Study of Spatial Systems in Human Geography. Londres: Methuen.
MLA-viite (9. p.)Hohnston, R.J, ja W.B. Pugh Morgan. Spatial Structures. Introducing the Study of Spatial Systems in Human Geography. Methuen.
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