Knuijt, M. (2012). Sharp as a Knife: The Dutch Waterline, a historic defence system, is nowadays a cultural heritage site which has been developed as an important recreational area. Topos.
Chicago-viite (17. p.)Knuijt, Martin. "Sharp as a Knife: The Dutch Waterline, a Historic Defence System, Is Nowadays a Cultural Heritage Site Which Has Been Developed as an Important Recreational Area." Topos 2012.
MLA-viite (8. p.)Knuijt, Martin. "Sharp as a Knife: The Dutch Waterline, a Historic Defence System, Is Nowadays a Cultural Heritage Site Which Has Been Developed as an Important Recreational Area." Topos, 2012.
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