@article{702371,
     title = {Preface},
     booktitle = {Equadiff 7},
     series = {GDML\_Books},
     publisher = {BSB B.G. Teubner Verlagsgesellschaft},
     address = {Leipzig},
     year = {1990},
     pages = {3-4},
     url = {http://dml.mathdoc.fr/item/702371}
}

 (éd.). Preface, dans Equadiff 7, GDML_Books,  (1990), pp. 3-4. http://gdmltest.u-ga.fr/item/702371/