Heckmann, FriedrichFriedrichHeckmann2019-09-192015-07-131997https://fis.uni-bamberg.de/handle/uniba/38233deuPatterns of immigrant integration in Germanyworkingpaperhttps://web.archive.org/web/20040214142120/http://www.uni-bamberg.de/~ba6ef3/pdf/efms_p14.pdf