@incollection{Das_j1995_a, author = {J{\"u}rgen~Dassow}, title = {{Cooperating grammar systems (Definitions, basic results, open problems)}}, booktitle = {{Artificial Life: Grammatical Models}}, publisher = {Black Sea University Press}, year = 1995, editor = {Gheorghe~P\u{a}un}, pages = {40--52} }