author = { Spencer-Brown, G. },

title = { Laws of form },

publisher = {Bohmeier},

isbn = {9783890945804},

keywords = { Form , Logikkalkül , Boolesche Algebra , Vierfarbensatz },

year = {2008},

address = { Leipzig },

url = { http://slubdd.de/katalog?TN_libero_mab2 }