@incollection { Luhmann1976,
 title = {Zur systemtheoretischen Konstruktion von Evolution},
 author = {Luhmann, Niklas},
 editor = {Lepsius, M. Rainer},
 pages = {49-52},
 year = {1976},
 publisher = {Ferdinand Enke},
 isbn = {3-432-88471-0},
 url = {http://nbn-resolving.de/urn:nbn:de:0168-ssoar-160613},
}