Compositionality: The Significant Difference International Symposium, COMPOS'97 Bad Malente, Germany, September 8-12, 1997 Revised Lectures - Roever, Willem-Paul de; Roever, Willem-Paul de; Langmaack, Hans; Langmaack, Hans; Pnueli, Amir; Pnueli, Amir (Springer Berlin Heidelberg : Imprint: Springer, 1998)