@techreport{LamMT01, author = {R. Lamour and R. M{\"a}rz and C. Tischendorf}, title = {{PDAEs} and Further Mixed Systems as Abstract Differential Algebraic Systems}, institution = {Inst. of Math.}, year = {2001}, number = {01-11}, address = {Humboldt Univ.\ of Berlin}, url = {http://www2.math.hu-berlin.de/publ/publ01.html} }