参考文献:
Vifor (International) AG Bark, Thomas Buhr, Wilm Burckhardt, Susanna Burgert, Michael Canclini, Camillo Dürrenberger, Franz Funk, Felix Geisser, Peter Kalogerakis, Aris Mayer, Simona Philipp, Erik Reim, Stefan Sieber, Diana Schmitt, Jörg Schwarz, Katrin Patent: US3/966 A, 3 Location in patent: Paragraph 35 353 354 355