@unpublished{ParkMuellerKirsten2000, author = {D.K. Park and H. J. W. M{\"u}ller-Kirsten}, title = {Universality or Non-Universality of Absorption Cross Sections for Extended Objects}, institution = {Fachbereich Physik}, year = {2000}, url = {http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:386-kluedo-11130}, }